diff --git a/Mlaumcherb.Client.Avalonia/Config.cs b/Mlaumcherb.Client.Avalonia/Config.cs
index 058dadd..9ac5748 100644
--- a/Mlaumcherb.Client.Avalonia/Config.cs
+++ b/Mlaumcherb.Client.Avalonia/Config.cs
@@ -1,10 +1,12 @@
 using Mlaumcherb.Client.Avalonia.зримое;
+using Mlaumcherb.Client.Avalonia.классы;
 using Mlaumcherb.Client.Avalonia.холопы;
 
 namespace Mlaumcherb.Client.Avalonia;
 
 public record Config
 {
+    [JsonRequired] public string config_version { get; set; } = "1.0.0";
     public bool debug { get; set; } = 
 #if DEBUG
         true;
@@ -17,6 +19,12 @@ public record Config
     public bool download_java { get; set; } = true;
     public string? last_launched_version { get; set; }
     public int max_parallel_downloads { get; set; } = 16;
+
+
+    public VersionCatalogProps[] version_catalogs { get; set; } =
+    [
+        new() { Name = "Mojang", Url = "https://piston-meta.mojang.com/mc/game/version_manifest_v2.json" }
+    ];
     
     [JsonIgnore] static IOPath _filePath = "config.json";
     
diff --git a/Mlaumcherb.Client.Avalonia/GameVersion.cs b/Mlaumcherb.Client.Avalonia/GameVersion.cs
index b257354..f1faacb 100644
--- a/Mlaumcherb.Client.Avalonia/GameVersion.cs
+++ b/Mlaumcherb.Client.Avalonia/GameVersion.cs
@@ -26,9 +26,9 @@ public class GameVersion
     private CancellationTokenSource? _gameCts;
     private CommandTask<CommandResult>? _commandTask;
 
-    public static async Task<List<GameVersionProps>> GetAllVersionsAsync()
+    public static Task<List<GameVersionProps>> GetAllVersionsAsync()
     {
-        var propsSet = new HashSet<GameVersionProps>();
+        var propsList = new List<GameVersionProps>();
         
         // local descriptors
         Directory.Create(GetVersionsDir());
@@ -38,19 +38,12 @@ public class GameVersion
             var d = new GameVersionProps(name, null);
             if(!File.Exists(d.LocalDescriptorPath))
                 throw new Exception("Can't find version descriptor file in directory '{subdir}'. Rename it as directory name.");
-            propsSet.Add(d);
-        }
-        
-        // remote non-duplicating versions
-        foreach (var removeVersion in await Сеть.GetDownloadableVersions())
-        {
-           propsSet.Add(removeVersion);
+            propsList.Add(d);
         }
         
         // reverse sort
-        var propsList = propsSet.ToList();
         propsList.Sort((a, b) => b.CompareTo(a));
-        return propsList;
+        return Task.FromResult(propsList);
     }
 
     public static async Task<GameVersion> CreateFromPropsAsync(GameVersionProps props)
@@ -60,7 +53,7 @@ public class GameVersion
             if (props.RemoteDescriptorUrl is null)
                 throw new NullReferenceException("can't download game version descriptor '"
                                                  + props.Name + "', because RemoteDescriptorUrl is null");
-            await Сеть.DownloadFile(props.RemoteDescriptorUrl, props.LocalDescriptorPath);
+            await NetworkHelper.DownloadFile(props.RemoteDescriptorUrl, props.LocalDescriptorPath);
         }
 
         return new GameVersion(props);
diff --git a/Mlaumcherb.Client.Avalonia/LauncherLogger.cs b/Mlaumcherb.Client.Avalonia/LauncherLogger.cs
index e1028f1..fcd8c83 100644
--- a/Mlaumcherb.Client.Avalonia/LauncherLogger.cs
+++ b/Mlaumcherb.Client.Avalonia/LauncherLogger.cs
@@ -1,6 +1,4 @@
-using Mlaumcherb.Client.Avalonia.зримое;
-
-namespace Mlaumcherb.Client.Avalonia;
+namespace Mlaumcherb.Client.Avalonia;
 
 public class LauncherLogger : ILogger
 {
diff --git a/Mlaumcherb.Client.Avalonia/зримое/MainWindow.axaml b/Mlaumcherb.Client.Avalonia/зримое/MainWindow.axaml
index 4cf3144..6d28e4c 100644
--- a/Mlaumcherb.Client.Avalonia/зримое/MainWindow.axaml
+++ b/Mlaumcherb.Client.Avalonia/зримое/MainWindow.axaml
@@ -7,53 +7,93 @@
         Title="млаумчерб"
         Icon="avares://млаумчерб/капитал/кубе.ico"
         FontFamily="{StaticResource MonospaceFont}" FontSize="18"
-        MinWidth="1200" MinHeight="700"
-        Width="800" Height="500"
+        MinWidth="800" MinHeight="400"
+        Width="800" Height="600"
         WindowStartupLocation="CenterScreen">
-    <Grid>
-        <Grid.RowDefinitions>* 30</Grid.RowDefinitions>
+    <Grid RowDefinitions="* 30">
         <Image Grid.RowSpan="2" Stretch="UniformToFill"
                Source="avares://млаумчерб/капитал/фоне.png"/>
         
         <Grid Grid.Row="0" Margin="10">
-            <Grid.ColumnDefinitions>* 300 *</Grid.ColumnDefinitions>
+            <Grid.ColumnDefinitions>
+                <ColumnDefinition MinWidth="150"/>
+                <ColumnDefinition Width="2" />
+                <ColumnDefinition MinWidth="300"/>
+                <ColumnDefinition Width="2" />
+                <ColumnDefinition MinWidth="150"/>
+            </Grid.ColumnDefinitions>
+            
+            <GridSplitter Grid.Column="1" Background="Transparent" ResizeDirection="Columns" />
+            <GridSplitter Grid.Column="3" Background="Transparent" ResizeDirection="Columns"/>
             
             <!-- Central panel -->
-            <Border Grid.Column="1" 
-                    Classes="dark_tr_bg white_border"
-                    Margin="10 0">
+            <Border Grid.Column="2"
+                    Classes="dark_tr_bg white_border">
                 <Grid>
                     <Grid.RowDefinitions>* 60</Grid.RowDefinitions>
-                    <StackPanel Orientation="Vertical" Margin="10" Spacing="10">
-                        <TextBlock>Версия:</TextBlock>
-                        <ComboBox Name="VersionComboBox"/>
-                        
-                        <TextBlock>Ник:</TextBlock>
-                        <TextBox Background="Transparent"
-                                 Text="{Binding #window.PlayerName}"/>
-                        
-                        <TextBlock>
-                            <Run>Выделенная память:</Run>
-                            <TextBox Background="Transparent" Padding="0"
-                                     BorderThickness="1"
-                                     BorderBrush="#777777"
-                                     Text="{Binding #window.MemoryLimit}">
-                            </TextBox>
-                            <Run>Мб</Run>
-                        </TextBlock>
-                        <Slider Minimum="2048" Maximum="8192"
-                                Value="{Binding #window.MemoryLimit}">
-                        </Slider>
-                        
-                        <CheckBox IsChecked="{Binding #window.CheckGameFiles}">
-                            Проверять файлы игры
-                        </CheckBox>
-                        <CheckBox IsChecked="{Binding #window.EnableJavaDownload}">
-                            Скачивать джаву
-                        </CheckBox>
-                    </StackPanel>
+                    <ScrollViewer Grid.Row="0" 
+                              HorizontalScrollBarVisibility="Disabled"
+                              VerticalScrollBarVisibility="Auto">
+                        <StackPanel Margin="10" Spacing="10">
+                            <TextBlock>Версия:</TextBlock>
+                            <ComboBox Name="InstalledVersionComboBox"/>
+                            <Button Name="DeleteVersionButton" 
+                                    Click="DeleteVersionButton_OnClick">
+                                Удалить версию
+                            </Button>
+                            
+                            <Expander Header="Добавление версий"
+                                      BorderThickness="1" BorderBrush="Gray"
+                                      Padding="4">
+                                <StackPanel>
+                                    <TextBlock>Источник:</TextBlock>
+                                    <ComboBox Name="VersionCatalogComboBox"/>
+                                    <WrapPanel>
+                                        <CheckBox Name="ReleaseVersionTypeCheckBox" IsChecked="True">релиз</CheckBox>
+                                        <CheckBox Name="SnapshotVersionTypeCheckBox">снапшот</CheckBox>
+                                        <CheckBox Name="OldVersionTypeCheckBox">старое</CheckBox>
+                                        <CheckBox Name="OtherVersionTypeAlphaCheckBox">другое</CheckBox>
+                                    </WrapPanel>
+                                    <Button Name="SearchVersionsButton"
+                                            Click="SearchVersionsButton_OnClick">
+                                        Поиск
+                                    </Button>
+                                    <TextBlock>Доступные версии:</TextBlock>
+                                    <ComboBox Name="VersionCatalogItemsComboBox"/>
+                                    <Button Name="AddVersionButton" IsEnabled="False"
+                                        Click="AddVersionButton_OnClick">
+                                        Добавить
+                                    </Button>
+                                </StackPanel>
+                            </Expander>
+                            
+                            <TextBlock>Ник:</TextBlock>
+                            <TextBox Background="Transparent"
+                                     Text="{Binding #window.PlayerName}"/>
+                            
+                            <TextBlock>
+                                <Run>Выделенная память:</Run>
+                                <TextBox Background="Transparent" Padding="0"
+                                         BorderThickness="1"
+                                         BorderBrush="#777777"
+                                         Text="{Binding #window.MemoryLimit}">
+                                </TextBox>
+                                <Run>Мб</Run>
+                            </TextBlock>
+                            <Slider Minimum="2048" Maximum="8192"
+                                    Value="{Binding #window.MemoryLimit}">
+                            </Slider>
+                            
+                            <CheckBox IsChecked="{Binding #window.CheckGameFiles}">
+                                Проверять файлы игры
+                            </CheckBox>
+                            <CheckBox IsChecked="{Binding #window.EnableJavaDownload}">
+                                Скачивать джаву
+                            </CheckBox>
+                        </StackPanel>
+                    </ScrollViewer>
                     <Button Name="LaunchButton" Grid.Row="1"
-                            Margin="10" Padding="0 0 0 4"
+                            Margin="10" Padding="4"
                             Classes="button_no_border"
                             Background="#BBfd7300"
                             Click="Запуск">
@@ -63,10 +103,9 @@
             </Border>
             
             <!-- Left panel -->
-            <Border Grid.Column="0" 
+            <Border Grid.Column="0"
                     Classes="dark_tr_bg white_border">
-                <Grid>
-                    <Grid.RowDefinitions>36 *</Grid.RowDefinitions>
+                <Grid RowDefinitions="36 *">
                     <Border Classes="white_border" Margin="-1" Padding="4">
                         <DockPanel>
                             <TextBlock FontWeight="Bold"
@@ -92,9 +131,9 @@
             </Border>
             
             <!-- Right panel -->
-            <Border Grid.Column="2" Classes="dark_tr_bg white_border">
-                <Grid>
-                    <Grid.RowDefinitions>36 *</Grid.RowDefinitions>
+            <Border Grid.Column="4"
+                    Classes="dark_tr_bg white_border">
+                <Grid RowDefinitions="36 *">
                     <Border Classes="white_border" Margin="-1" Padding="4">
                         <DockPanel>
                             <TextBlock FontWeight="Bold"
diff --git a/Mlaumcherb.Client.Avalonia/зримое/MainWindow.axaml.cs b/Mlaumcherb.Client.Avalonia/зримое/MainWindow.axaml.cs
index 238eabe..8331afd 100644
--- a/Mlaumcherb.Client.Avalonia/зримое/MainWindow.axaml.cs
+++ b/Mlaumcherb.Client.Avalonia/зримое/MainWindow.axaml.cs
@@ -6,6 +6,9 @@ using Avalonia.Platform.Storage;
 using Avalonia.Threading;
 using Mlaumcherb.Client.Avalonia.классы;
 using Mlaumcherb.Client.Avalonia.холопы;
+using MsBox.Avalonia;
+using MsBox.Avalonia.Dto;
+using MsBox.Avalonia.Models;
 
 namespace Mlaumcherb.Client.Avalonia.зримое;
 
@@ -63,19 +66,26 @@ public partial class MainWindow : Window
             MemoryLimit = LauncherApp.Config.max_memory;
             EnableJavaDownload = LauncherApp.Config.download_java;
 
-            VersionComboBox.SelectedIndex = 0;
-            VersionComboBox.IsEnabled = false;
+            InstalledVersionComboBox.SelectedIndex = 0;
+            InstalledVersionComboBox.IsEnabled = false;
             var versions = await GameVersion.GetAllVersionsAsync();
             Dispatcher.UIThread.Invoke(() =>
             {
                 foreach (var p in versions)
                 {
-                    VersionComboBox.Items.Add(new VersionItemView(p));
+                    InstalledVersionComboBox.Items.Add(new VersionItemView(p));
+                    // select last played version
                     if (LauncherApp.Config.last_launched_version != null &&
                         p.Name == LauncherApp.Config.last_launched_version)
-                        VersionComboBox.SelectedIndex = VersionComboBox.Items.Count - 1;
+                        InstalledVersionComboBox.SelectedIndex = InstalledVersionComboBox.Items.Count - 1;
                 }
-                VersionComboBox.IsEnabled = true;
+                InstalledVersionComboBox.IsEnabled = true;
+
+                foreach (var vc in LauncherApp.Config.version_catalogs)
+                {
+                    VersionCatalogComboBox.Items.Add(vc);
+                }
+                VersionCatalogComboBox.SelectedIndex = 0;
             });
         }
         catch (Exception ex)
@@ -103,7 +113,7 @@ public partial class MainWindow : Window
         {
             Dispatcher.UIThread.Invoke(() => LaunchButton.IsEnabled = false);
             
-            var selectedVersionView = (VersionItemView?)VersionComboBox.SelectedItem;
+            var selectedVersionView = (VersionItemView?)InstalledVersionComboBox.SelectedItem;
             var selectedVersion = selectedVersionView?.Props;
             LauncherApp.Config.last_launched_version = selectedVersion?.Name;
             LauncherApp.Config.player_name = PlayerName;
@@ -196,4 +206,94 @@ public partial class MainWindow : Window
         }
         DownloadsPanel.Children.Clear();
     }
+
+    private async void DeleteVersionButton_OnClick(object? sender, RoutedEventArgs e)
+    {
+        try
+        {
+            VersionItemView? sel = InstalledVersionComboBox.SelectedItem as VersionItemView;
+            if(sel is null)
+                return;
+        
+            var box = MessageBoxManager.GetMessageBoxCustom(new MessageBoxCustomParams
+                {
+                    ButtonDefinitions = new List<ButtonDefinition> { new() { Name = "Да" }, new() { Name = "Нет" } },
+                    ContentTitle = $"Удаление версии {sel.Props.Name}",
+                    ContentMessage = $"Вы уверены, что хотите удалить версию {sel.Props.Name}? Все файлы, включая сохранения, будут удалены!",
+                    Icon = MsBox.Avalonia.Enums.Icon.Question,
+                    WindowStartupLocation = WindowStartupLocation.CenterOwner,
+                    SizeToContent = SizeToContent.WidthAndHeight,
+                    ShowInCenter = true,
+                    Topmost = true
+                }
+            );
+            var result = await box.ShowAsync().ConfigureAwait(false);
+            if (result != "Да") 
+                return;
+            
+            sel.Props.DeleteFiles();
+            Dispatcher.UIThread.Invoke(() =>
+            {
+                InstalledVersionComboBox.Items.Remove(sel);
+            });
+        }
+        catch (Exception ex)
+        {
+            ErrorHelper.ShowMessageBox(nameof(MainWindow), ex);
+        }
+    }
+    
+    private async void SearchVersionsButton_OnClick(object? sender, RoutedEventArgs e)
+    {
+        try 
+        {
+            var catalogProps = VersionCatalogComboBox.SelectedItem as VersionCatalogProps;
+            if(catalogProps is null)
+                return;
+
+            var catalog = await catalogProps.GetVersionCatalogAsync();
+            var searchParams = new VersionSearchParams();
+            Dispatcher.UIThread.Invoke(() =>
+            {
+                searchParams.ReleaseTypeAllowed = ReleaseVersionTypeCheckBox.IsChecked ?? false;
+                searchParams.SnapshotTypeAllowed = SnapshotVersionTypeCheckBox.IsChecked ?? false;
+                searchParams.OldTypeAllowed = OldVersionTypeCheckBox.IsChecked ?? false;
+                searchParams.OtherTypeAllowed = OtherVersionTypeAlphaCheckBox.IsChecked ?? false;
+            });
+            var versions = catalog.GetDownloadableVersions(searchParams);
+            
+            Dispatcher.UIThread.Invoke(() =>
+            {
+                VersionCatalogItemsComboBox.IsEnabled = false;
+                VersionCatalogItemsComboBox.Items.Clear();
+                foreach (var p in versions)
+                {
+                    VersionCatalogItemsComboBox.Items.Add(new VersionItemView(p));
+                }
+                VersionCatalogItemsComboBox.IsEnabled = true;
+                AddVersionButton.IsEnabled = versions.Count > 0;
+            });
+        }
+        catch (Exception ex)
+        {
+           ErrorHelper.ShowMessageBox(nameof(MainWindow), ex);
+        }
+    }
+
+    private void AddVersionButton_OnClick(object? sender, RoutedEventArgs e)
+    {
+        try
+        {
+            var selectedVersionView = VersionCatalogItemsComboBox.SelectedItem as VersionItemView;
+            if(selectedVersionView is null)
+                return;
+            
+            InstalledVersionComboBox.Items.Insert(0, new VersionItemView(selectedVersionView.Props));
+            InstalledVersionComboBox.SelectedIndex = 0;
+        }
+        catch (Exception ex)
+        {
+            ErrorHelper.ShowMessageBox(nameof(MainWindow), ex);
+        }
+    }
 }
\ No newline at end of file
diff --git a/Mlaumcherb.Client.Avalonia/зримое/VersionItemView.axaml b/Mlaumcherb.Client.Avalonia/зримое/VersionItemView.axaml
index 077aae5..be8ee04 100644
--- a/Mlaumcherb.Client.Avalonia/зримое/VersionItemView.axaml
+++ b/Mlaumcherb.Client.Avalonia/зримое/VersionItemView.axaml
@@ -4,6 +4,7 @@
              xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
              xmlns:local="clr-namespace:Mlaumcherb.Client.Avalonia"
              mc:Ignorable="d" d:DesignWidth="800" d:DesignHeight="450"
-             x:Class="Mlaumcherb.Client.Avalonia.зримое.VersionItemView">
+             x:Class="Mlaumcherb.Client.Avalonia.зримое.VersionItemView"
+             Padding="2">
     <TextBlock Name="text" Background="Transparent"/>
 </UserControl>
diff --git a/Mlaumcherb.Client.Avalonia/зримое/VersionItemView.axaml.cs b/Mlaumcherb.Client.Avalonia/зримое/VersionItemView.axaml.cs
index 11260ff..3f30014 100644
--- a/Mlaumcherb.Client.Avalonia/зримое/VersionItemView.axaml.cs
+++ b/Mlaumcherb.Client.Avalonia/зримое/VersionItemView.axaml.cs
@@ -1,5 +1,6 @@
 using Avalonia.Controls;
 using Avalonia.Media;
+using Avalonia.Threading;
 using Mlaumcherb.Client.Avalonia.классы;
 
 namespace Mlaumcherb.Client.Avalonia.зримое;
@@ -20,12 +21,14 @@ public partial class VersionItemView : ListBoxItem
         Props = props;
         InitializeComponent();
         text.Text = props.Name;
-        props.OnDownloadCompleted += UpdateBackground;
-        UpdateBackground();
+        props.StatusChanged += UpdateBackground;
+        UpdateBackground(props.IsDownloaded);
     }
 
-    private void UpdateBackground()
+    private void UpdateBackground(bool isDownloaded)
     {
-        Background = Props.IsDownloaded ? _avaliableColor : _unavaliableColor;
+        Dispatcher.UIThread.Invoke(() => 
+            Background = isDownloaded ? _avaliableColor : _unavaliableColor
+        );
     }
 }
\ No newline at end of file
diff --git a/Mlaumcherb.Client.Avalonia/классы/Буржуазия/GameVersionCatalog.cs b/Mlaumcherb.Client.Avalonia/классы/Буржуазия/GameVersionCatalog.cs
index d1dcc8a..5c7869b 100644
--- a/Mlaumcherb.Client.Avalonia/классы/Буржуазия/GameVersionCatalog.cs
+++ b/Mlaumcherb.Client.Avalonia/классы/Буржуазия/GameVersionCatalog.cs
@@ -1,8 +1,35 @@
 namespace Mlaumcherb.Client.Avalonia.классы;
 
+public record VersionSearchParams
+{
+    public bool ReleaseTypeAllowed;
+    public bool SnapshotTypeAllowed;
+    public bool OldTypeAllowed;
+    public bool OtherTypeAllowed;
+}
+
 public class GameVersionCatalog
 {
     [JsonRequired] public List<RemoteVersionDescriptorProps> versions { get; set; } = null!;
+    
+    /// <returns>empty list if couldn't find any remote versions</returns>
+    public List<GameVersionProps> GetDownloadableVersions(VersionSearchParams p)
+    {
+        var _versionPropsList = new List<GameVersionProps>();
+        foreach (var r in versions)
+        {
+            bool match = r.type switch
+            {
+                "release" => p.ReleaseTypeAllowed,
+                "snapshot" => p.SnapshotTypeAllowed,
+                "old_alpha" or "old_beta" => p.OldTypeAllowed,
+                _ => p.OtherTypeAllowed
+            };
+            if(match)
+                _versionPropsList.Add(new GameVersionProps(r.id, r.url));
+        }
+        return _versionPropsList;
+    }
 }
 
 public class AssetProperties
@@ -19,9 +46,9 @@ public class AssetIndex
 public class RemoteVersionDescriptorProps
 {
     [JsonRequired] public string id { get; set; } = "";
-    [JsonRequired] public string type { get; set; } = "";
     [JsonRequired] public string url { get; set; } = "";
-    [JsonRequired] public string sha1 { get; set; } = "";
-    [JsonRequired] public DateTime time { get; set; }
-    [JsonRequired] public DateTime releaseTime { get; set; }
+    [JsonRequired] public string type { get; set; } = "";
+    public string sha1 { get; set; } = "";
+    public DateTime time { get; set; }
+    public DateTime releaseTime { get; set; }
 }
diff --git a/Mlaumcherb.Client.Avalonia/классы/Буржуазия/GameVersionDescriptor.cs b/Mlaumcherb.Client.Avalonia/классы/Буржуазия/GameVersionDescriptor.cs
index a5d26bd..2adc318 100644
--- a/Mlaumcherb.Client.Avalonia/классы/Буржуазия/GameVersionDescriptor.cs
+++ b/Mlaumcherb.Client.Avalonia/классы/Буржуазия/GameVersionDescriptor.cs
@@ -10,10 +10,10 @@ public class GameVersionDescriptor
     [JsonRequired] public DateTime releaseTime { get; set; }
     [JsonRequired] public string type { get; set; } = "";
     [JsonRequired] public string mainClass { get; set; } = "";
-    [JsonRequired] public Downloads downloads { get; set; } = null!;
     [JsonRequired] public List<Library> libraries { get; set; } = null!;
     [JsonRequired] public AssetIndexProperties assetIndex { get; set; } = null!;
     [JsonRequired] public string assets { get; set; } = "";
+    public Downloads? downloads { get; set; } = null;
     public JavaVersion javaVersion { get; set; } = new() { component = "jre-legacy", majorVersion = 8 };
     public string? minecraftArguments { get; set; }
     public ArgumentsNew? arguments { get; set; }
diff --git a/Mlaumcherb.Client.Avalonia/классы/Пролетариат/GameVersionProps.cs b/Mlaumcherb.Client.Avalonia/классы/Пролетариат/GameVersionProps.cs
index 1204df6..c360d5f 100644
--- a/Mlaumcherb.Client.Avalonia/классы/Пролетариат/GameVersionProps.cs
+++ b/Mlaumcherb.Client.Avalonia/классы/Пролетариат/GameVersionProps.cs
@@ -1,4 +1,5 @@
-using Mlaumcherb.Client.Avalonia.холопы;
+using Mlaumcherb.Client.Avalonia.зримое;
+using Mlaumcherb.Client.Avalonia.холопы;
 
 namespace Mlaumcherb.Client.Avalonia.классы;
 
@@ -13,13 +14,14 @@ public class GameVersionProps : IComparable<GameVersionProps>, IEquatable<GameVe
         get => _isDownloaded;
         set
         {
-            bool downloadCompleted = value && !_isDownloaded;
-            _isDownloaded = value;
-            if(downloadCompleted)
-                OnDownloadCompleted?.Invoke();
+            if(_isDownloaded != value)
+            {
+                _isDownloaded = value;
+                StatusChanged?.Invoke(value);
+            }
         }
     }
-    public event Action? OnDownloadCompleted;
+    public event Action<bool>? StatusChanged;
 
     public GameVersionProps(string name, string? url)
     {
@@ -29,6 +31,16 @@ public class GameVersionProps : IComparable<GameVersionProps>, IEquatable<GameVe
         IsDownloaded = File.Exists(PathHelper.GetVersionJarFilePath(name));
     }
 
+    public void DeleteFiles()
+    {
+        IsDownloaded = false;
+        LauncherApp.Logger.LogInfo(Name, "Deleting files...");
+        var verdir = PathHelper.GetVersionDir(Name);
+        if(Directory.Exists(verdir))
+            Directory.Delete(verdir);
+        LauncherApp.Logger.LogInfo(Name, "Files deleted");
+    }
+    
     public override string ToString() => Name;
 
     public override int GetHashCode() => Name.GetHashCode();
diff --git a/Mlaumcherb.Client.Avalonia/классы/Пролетариат/Libraries.cs b/Mlaumcherb.Client.Avalonia/классы/Пролетариат/Libraries.cs
index 4cf2f00..bf221f8 100644
--- a/Mlaumcherb.Client.Avalonia/классы/Пролетариат/Libraries.cs
+++ b/Mlaumcherb.Client.Avalonia/классы/Пролетариат/Libraries.cs
@@ -7,11 +7,19 @@ public class Libraries
 {
     private static readonly string[] enabled_features = [];
     
-    public record JarLib(string name, IOPath jarFilePath, Artifact artifact);
-    public record NativeLib(string name, IOPath jarFilePath, Artifact artifact, Extract? extractionOptions) 
+    public record JarLib(string name, IOPath? jarFilePath, Artifact artifact);
+    public record NativeLib(string name, IOPath? jarFilePath, Artifact artifact, Extract? extractionOptions) 
         : JarLib(name, jarFilePath, artifact);
     
     public IReadOnlyCollection<JarLib> Libs { get; }
+
+    private IOPath? TryGetJarFilePath(Artifact artifact)
+    {
+        if(string.IsNullOrEmpty(artifact.url))
+            return null;
+        string urlTail = artifact.url.AsSpan().After("://").After('/').ToString();
+        return Path.Concat(PathHelper.GetLibrariesDir(), urlTail);
+    }
     
     public Libraries(GameVersionDescriptor descriptor)
     {
@@ -54,10 +62,8 @@ public class Libraries
                 // skipping duplicates (WHO THE HELL CREATES THIS DISCRIPTORS AAAAAAAAA)
                 if(!libHashes.Add(artifact.sha1))
                     continue;
-
-                string urlTail = artifact.url.AsSpan().After("://").After('/').ToString();
-                IOPath jarFilePath = Path.Concat(PathHelper.GetLibrariesDir(), urlTail);
-                libs.Add(new NativeLib(l.name, jarFilePath, artifact, l.extract));
+                
+                libs.Add(new NativeLib(l.name, TryGetJarFilePath(artifact), artifact, l.extract));
             }
             else
             {
@@ -69,9 +75,7 @@ public class Libraries
                 if(!libHashes.Add(artifact.sha1))
                     continue;
                 
-                string urlTail = artifact.url.AsSpan().After("://").After('/').ToString();
-                IOPath jarFilePath = Path.Concat(PathHelper.GetLibrariesDir(), urlTail);
-                libs.Add(new JarLib(l.name, jarFilePath, artifact));
+                libs.Add(new JarLib(l.name, TryGetJarFilePath(artifact), artifact));
             }
         }
 
diff --git a/Mlaumcherb.Client.Avalonia/классы/Пролетариат/VersionCatalogProps.cs b/Mlaumcherb.Client.Avalonia/классы/Пролетариат/VersionCatalogProps.cs
new file mode 100644
index 0000000..c72a9c1
--- /dev/null
+++ b/Mlaumcherb.Client.Avalonia/классы/Пролетариат/VersionCatalogProps.cs
@@ -0,0 +1,18 @@
+using Mlaumcherb.Client.Avalonia.сеть;
+
+namespace Mlaumcherb.Client.Avalonia.классы;
+
+
+public class VersionCatalogProps
+{
+    [JsonRequired] public required string Name { get; init; }
+    [JsonRequired] public required string Url { get; init; }
+        
+    public override string ToString() => Name;
+    
+    
+    public async Task<GameVersionCatalog> GetVersionCatalogAsync()
+    {
+        return await NetworkHelper.DownloadStringAndDeserialize<GameVersionCatalog>(Url);
+    }
+}
\ No newline at end of file
diff --git a/Mlaumcherb.Client.Avalonia/сеть/Сеть.cs b/Mlaumcherb.Client.Avalonia/сеть/NetworkHelper.cs
similarity index 51%
rename from Mlaumcherb.Client.Avalonia/сеть/Сеть.cs
rename to Mlaumcherb.Client.Avalonia/сеть/NetworkHelper.cs
index ee34e65..32803a0 100644
--- a/Mlaumcherb.Client.Avalonia/сеть/Сеть.cs
+++ b/Mlaumcherb.Client.Avalonia/сеть/NetworkHelper.cs
@@ -4,11 +4,11 @@ using Mlaumcherb.Client.Avalonia.классы;
 
 namespace Mlaumcherb.Client.Avalonia.сеть;
 
-public static class Сеть
+public static class NetworkHelper
 {
     private static HttpClient _http = new();
 
-    static Сеть()
+    static NetworkHelper()
     {
         // thanks for Sashok :3
         // https://github.com/new-sashok724/Launcher/blob/23485c3f7de6620d2c6b7b2dd9339c3beb6a0366/Launcher/source/helper/IOHelper.java#L259
@@ -36,52 +36,9 @@ public static class Сеть
     
     public static async Task<T> DownloadStringAndDeserialize<T>(string url)
     {
-        var text = await _http.GetStringAsync(url);
+        var text = await GetString(url);
         var result = JsonConvert.DeserializeObject<T>(text)
             ?? throw new Exception($"can't deserialize {typeof(T).Name}");
         return result;
     }
-    
-    private static readonly string[] VERSION_MANIFEST_URLS =
-    {
-        "https://piston-meta.mojang.com/mc/game/version_manifest_v2.json"
-    };
-
-    private static async Task<List<RemoteVersionDescriptorProps>> GetRemoteVersionDescriptorsAsync()
-    {
-        List<RemoteVersionDescriptorProps> descriptors = new();
-        foreach (var url in VERSION_MANIFEST_URLS)
-        {
-            try
-            {
-                var catalog = await DownloadStringAndDeserialize<GameVersionCatalog>(url);
-                descriptors.AddRange(catalog.versions);
-            }
-            catch (Exception ex)
-            {
-                LauncherApp.Logger.LogWarn(nameof(Сеть), ex);
-            }
-        }
-
-        return descriptors;
-    }
-
-    private static List<GameVersionProps>? _versionPropsList;
-
-    /// <returns>empty list if couldn't find any remote versions</returns>
-    public static async Task<IReadOnlyList<GameVersionProps>> GetDownloadableVersions()
-    {
-        if (_versionPropsList == null)
-        {
-            _versionPropsList = new();
-            var rvdlist = await GetRemoteVersionDescriptorsAsync();
-            foreach (var r in rvdlist)
-            {
-                if (r.type == "release")
-                    _versionPropsList.Add(new GameVersionProps(r.id, r.url));
-            }
-        }
-
-        return _versionPropsList;
-    }
 }
\ No newline at end of file
diff --git a/Mlaumcherb.Client.Avalonia/сеть/TaskFactories/AssetsDownloadTaskFactory.cs b/Mlaumcherb.Client.Avalonia/сеть/TaskFactories/AssetsDownloadTaskFactory.cs
index 446e821..5d5212f 100644
--- a/Mlaumcherb.Client.Avalonia/сеть/TaskFactories/AssetsDownloadTaskFactory.cs
+++ b/Mlaumcherb.Client.Avalonia/сеть/TaskFactories/AssetsDownloadTaskFactory.cs
@@ -5,7 +5,7 @@ using DTLib.Extensions;
 using Mlaumcherb.Client.Avalonia.зримое;
 using Mlaumcherb.Client.Avalonia.классы;
 using Mlaumcherb.Client.Avalonia.холопы;
-using static Mlaumcherb.Client.Avalonia.сеть.Сеть;
+using static Mlaumcherb.Client.Avalonia.сеть.NetworkHelper;
 
 namespace Mlaumcherb.Client.Avalonia.сеть.TaskFactories;
 
@@ -39,9 +39,9 @@ public class AssetsDownloadTaskFactory : INetworkTaskFactory
     {
         if(!File.Exists(_indexFilePath))
         {
-            LauncherApp.Logger.LogInfo(nameof(Сеть), $"started downloading asset index to '{_indexFilePath}'");
+            LauncherApp.Logger.LogInfo(nameof(NetworkHelper), $"started downloading asset index to '{_indexFilePath}'");
             await DownloadFile(_descriptor.assetIndex.url, _indexFilePath);
-            LauncherApp.Logger.LogInfo(nameof(Сеть), "finished downloading asset index");
+            LauncherApp.Logger.LogInfo(nameof(NetworkHelper), "finished downloading asset index");
         }
 
         string indexFileText = File.ReadAllText(_indexFilePath);
@@ -102,7 +102,7 @@ public class AssetsDownloadTaskFactory : INetworkTaskFactory
     
     private async Task Download(NetworkProgressReporter pr, CancellationToken ct)
     {
-        LauncherApp.Logger.LogInfo(nameof(Сеть), $"started downloading assets '{_descriptor.assetIndex.id}'");
+        LauncherApp.Logger.LogInfo(nameof(NetworkHelper), $"started downloading assets '{_descriptor.assetIndex.id}'");
         ParallelOptions opt = new()
         {
             MaxDegreeOfParallelism = LauncherApp.Config.max_parallel_downloads,
@@ -114,7 +114,7 @@ public class AssetsDownloadTaskFactory : INetworkTaskFactory
             bool completed = false;
             while(!completed)
             {
-                LauncherApp.Logger.LogDebug(nameof(Сеть), $"downloading asset '{a.name}' {a.hash}");
+                LauncherApp.Logger.LogDebug(nameof(NetworkHelper), $"downloading asset '{a.name}' {a.hash}");
                 try
                 {
                     await DownloadFile(a.url, a.filePath, _ct, pr.AddBytesCount);
@@ -125,13 +125,13 @@ public class AssetsDownloadTaskFactory : INetworkTaskFactory
                     // wait on rate limit
                     if(httpException.StatusCode == HttpStatusCode.TooManyRequests)
                     {
-                        LauncherApp.Logger.LogDebug(nameof(Сеть), "rate limit hit");
+                        LauncherApp.Logger.LogDebug(nameof(NetworkHelper), "rate limit hit");
                         await Task.Delay(1000, _ct);
                     }
                     else throw;
                 }
             }
         });
-        LauncherApp.Logger.LogInfo(nameof(Сеть), $"finished downloading assets '{_descriptor.assetIndex.id}'");
+        LauncherApp.Logger.LogInfo(nameof(NetworkHelper), $"finished downloading assets '{_descriptor.assetIndex.id}'");
     }
 }
\ No newline at end of file
diff --git a/Mlaumcherb.Client.Avalonia/сеть/TaskFactories/JavaDownloadTaskFactory.cs b/Mlaumcherb.Client.Avalonia/сеть/TaskFactories/JavaDownloadTaskFactory.cs
index e1eb1c5..0486480 100644
--- a/Mlaumcherb.Client.Avalonia/сеть/TaskFactories/JavaDownloadTaskFactory.cs
+++ b/Mlaumcherb.Client.Avalonia/сеть/TaskFactories/JavaDownloadTaskFactory.cs
@@ -3,7 +3,7 @@ using DTLib.Extensions;
 using Mlaumcherb.Client.Avalonia.зримое;
 using Mlaumcherb.Client.Avalonia.классы;
 using Mlaumcherb.Client.Avalonia.холопы;
-using static Mlaumcherb.Client.Avalonia.сеть.Сеть;
+using static Mlaumcherb.Client.Avalonia.сеть.NetworkHelper;
 
 namespace Mlaumcherb.Client.Avalonia.сеть.TaskFactories;
 
@@ -84,7 +84,7 @@ public class JavaDownloadTaskFactory : INetworkTaskFactory
 
     private async Task Download(NetworkProgressReporter pr, CancellationToken ct)
     {
-        LauncherApp.Logger.LogInfo(nameof(Сеть), "started downloading java runtime " +
+        LauncherApp.Logger.LogInfo(nameof(NetworkHelper), "started downloading java runtime " +
                     $"{_descriptor.javaVersion.majorVersion} '{_descriptor.javaVersion.component}'");
         
         ParallelOptions opt = new()
@@ -96,7 +96,7 @@ public class JavaDownloadTaskFactory : INetworkTaskFactory
         {
             if (f.props.downloads!.lzma != null)
             {
-                LauncherApp.Logger.LogDebug(nameof(Сеть), $"downloading lzma-compressed file '{f.path}'");
+                LauncherApp.Logger.LogDebug(nameof(NetworkHelper), $"downloading lzma-compressed file '{f.path}'");
                 await using var pipe = new TransformStream(await GetStream(f.props.downloads.lzma.url, _ct));
                 pipe.AddTransform(pr.AddBytesCount);
                 await using var fs = File.OpenWrite(f.path);
@@ -104,18 +104,18 @@ public class JavaDownloadTaskFactory : INetworkTaskFactory
             }
             else
             {
-                LauncherApp.Logger.LogDebug(nameof(Сеть), $"downloading raw file '{f.path}'");
+                LauncherApp.Logger.LogDebug(nameof(NetworkHelper), $"downloading raw file '{f.path}'");
                 await DownloadFile(f.props.downloads.raw.url, f.path, _ct, pr.AddBytesCount);
             }
             
             if(!OperatingSystem.IsWindows() && f.props.executable is true)
             {
-                LauncherApp.Logger.LogDebug(nameof(Сеть), $"adding execute rights to file '{f.path}'");
+                LauncherApp.Logger.LogDebug(nameof(NetworkHelper), $"adding execute rights to file '{f.path}'");
                 System.IO.File.SetUnixFileMode(f.path.ToString(), UnixFileMode.UserExecute);
             }
         });
         
-        LauncherApp.Logger.LogInfo(nameof(Сеть), "finished downloading java runtime " + 
+        LauncherApp.Logger.LogInfo(nameof(NetworkHelper), "finished downloading java runtime " + 
                     $"{_descriptor.javaVersion.majorVersion} '{_descriptor.javaVersion.component}'");
     }
     
diff --git a/Mlaumcherb.Client.Avalonia/сеть/TaskFactories/LibrariesDownloadTaskFactory.cs b/Mlaumcherb.Client.Avalonia/сеть/TaskFactories/LibrariesDownloadTaskFactory.cs
index e27b9a0..ed54ab7 100644
--- a/Mlaumcherb.Client.Avalonia/сеть/TaskFactories/LibrariesDownloadTaskFactory.cs
+++ b/Mlaumcherb.Client.Avalonia/сеть/TaskFactories/LibrariesDownloadTaskFactory.cs
@@ -4,7 +4,7 @@ using DTLib.Extensions;
 using Mlaumcherb.Client.Avalonia.зримое;
 using Mlaumcherb.Client.Avalonia.классы;
 using Mlaumcherb.Client.Avalonia.холопы;
-using static Mlaumcherb.Client.Avalonia.сеть.Сеть;
+using static Mlaumcherb.Client.Avalonia.сеть.NetworkHelper;
 
 namespace Mlaumcherb.Client.Avalonia.сеть.TaskFactories;
 
@@ -43,7 +43,15 @@ public class LibrariesDownloadTaskFactory : INetworkTaskFactory
         
         foreach (var l in _libraries.Libs)
         {
-            if (!File.Exists(l.jarFilePath))
+            // Forge installer downloads some libraries manually.
+            // Such libraries have empty url in descriptor.
+            if(l.jarFilePath is null)
+            {
+                LauncherApp.Logger.LogDebug(nameof(NetworkHelper), $"library artifact has empty url: '{l.name}'");
+                continue;
+            }
+            
+            if (!File.Exists(l.jarFilePath.Value))
             {
                 _libsToDownload.Add(l);
             }
@@ -53,7 +61,7 @@ public class LibrariesDownloadTaskFactory : INetworkTaskFactory
             }
             else if (checkHashes)
             {
-                using var fs = File.OpenRead(l.jarFilePath);
+                using var fs = File.OpenRead(l.jarFilePath.Value);
                 string hash = _hasher.ComputeHash(fs).HashToString();
                 if(hash != l.artifact.sha1)
                     _libsToDownload.Add(l);
@@ -73,7 +81,7 @@ public class LibrariesDownloadTaskFactory : INetworkTaskFactory
 
     private async Task Download(NetworkProgressReporter pr, CancellationToken ct)
     {
-        LauncherApp.Logger.LogInfo(nameof(Сеть), $"started downloading libraries '{_descriptor.id}'");
+        LauncherApp.Logger.LogInfo(nameof(NetworkHelper), $"started downloading libraries '{_descriptor.id}'");
         
         ParallelOptions opt = new()
         {
@@ -82,11 +90,13 @@ public class LibrariesDownloadTaskFactory : INetworkTaskFactory
         };
         await Parallel.ForEachAsync(_libsToDownload, opt, async (l, _ct) =>
         {
-            LauncherApp.Logger.LogDebug(nameof(Сеть), $"downloading library '{l.name}' to '{l.jarFilePath}'");
-            await DownloadFile(l.artifact.url, l.jarFilePath, _ct, pr.AddBytesCount);
+            LauncherApp.Logger.LogDebug(nameof(NetworkHelper), $"downloading library '{l.name}' to '{l.jarFilePath}'");
+            if(l.jarFilePath is null)
+                throw new Exception("jarFilePath is null");
+            await DownloadFile(l.artifact.url, l.jarFilePath.Value, _ct, pr.AddBytesCount);
             if (l is Libraries.NativeLib n)
             {
-                var zipf = File.OpenRead(n.jarFilePath);
+                var zipf = File.OpenRead(n.jarFilePath!.Value);
                 ZipFile.ExtractToDirectory(zipf, _nativesDir.ToString(), true);
                 if (n.extractionOptions?.exclude != null)
                 {
@@ -102,6 +112,6 @@ public class LibrariesDownloadTaskFactory : INetworkTaskFactory
             }
         });
         
-        LauncherApp.Logger.LogInfo(nameof(Сеть), $"finished downloading libraries '{_descriptor.id}'");
+        LauncherApp.Logger.LogInfo(nameof(NetworkHelper), $"finished downloading libraries '{_descriptor.id}'");
     }
 }
\ No newline at end of file
diff --git a/Mlaumcherb.Client.Avalonia/сеть/TaskFactories/VersionFileDownloadTaskFactory.cs b/Mlaumcherb.Client.Avalonia/сеть/TaskFactories/VersionFileDownloadTaskFactory.cs
index b23fc21..31d8a09 100644
--- a/Mlaumcherb.Client.Avalonia/сеть/TaskFactories/VersionFileDownloadTaskFactory.cs
+++ b/Mlaumcherb.Client.Avalonia/сеть/TaskFactories/VersionFileDownloadTaskFactory.cs
@@ -3,7 +3,7 @@ using DTLib.Extensions;
 using Mlaumcherb.Client.Avalonia.зримое;
 using Mlaumcherb.Client.Avalonia.классы;
 using Mlaumcherb.Client.Avalonia.холопы;
-using static Mlaumcherb.Client.Avalonia.сеть.Сеть;
+using static Mlaumcherb.Client.Avalonia.сеть.NetworkHelper;
 
 namespace Mlaumcherb.Client.Avalonia.сеть.TaskFactories;
 
@@ -36,8 +36,13 @@ public class VersionFileDownloadTaskFactory : INetworkTaskFactory
     {
         if (!File.Exists(_filePath))
             return false;
+        
         if (!checkHashes)
             return true;
+
+        if (_descriptor.downloads is null)
+            return true;
+        
         using var fs = File.OpenRead(_filePath);
         string hash = _hasher.ComputeHash(fs).HashToString();
         return hash == _descriptor.downloads.client.sha1;
@@ -45,13 +50,18 @@ public class VersionFileDownloadTaskFactory : INetworkTaskFactory
 
     private long GetTotalSize()
     {
+        if(_descriptor.downloads is null)
+            return 0;
         return _descriptor.downloads.client.size;
     }
     
     private async Task Download(NetworkProgressReporter pr, CancellationToken ct)
     {
-        LauncherApp.Logger.LogInfo(nameof(Сеть), $"started downloading version file '{_descriptor.id}'");
+        if (_descriptor.downloads is null)
+            throw new Exception($"can't download version file '{_descriptor.id}' because it has no download url");
+        
+        LauncherApp.Logger.LogInfo(nameof(NetworkHelper), $"started downloading version file '{_descriptor.id}'");
         await DownloadFile(_descriptor.downloads.client.url, _filePath, ct, pr.AddBytesCount);
-        LauncherApp.Logger.LogInfo(nameof(Сеть), $"finished downloading version file '{_descriptor.id}'");
+        LauncherApp.Logger.LogInfo(nameof(NetworkHelper), $"finished downloading version file '{_descriptor.id}'");
     }
 }
\ No newline at end of file