diff --git a/CUE4Parse b/CUE4Parse
index b8d74d54..12ed351a 160000
--- a/CUE4Parse
+++ b/CUE4Parse
@@ -1 +1 @@
-Subproject commit b8d74d541e711481a569d712db9d38b17d130ff1
+Subproject commit 12ed351a1f623e042dfca16775072a1d652b8560
diff --git a/FModel/FModel.csproj b/FModel/FModel.csproj
index 8a153b12..e5bc0c2f 100644
--- a/FModel/FModel.csproj
+++ b/FModel/FModel.csproj
@@ -6,8 +6,8 @@
     <UseWPF>true</UseWPF>
     <ApplicationIcon>FModel.ico</ApplicationIcon>
     <Version>4.1.0</Version>
-    <AssemblyVersion>4.1.0.1</AssemblyVersion>
-    <FileVersion>4.1.0.1</FileVersion>
+    <AssemblyVersion>4.1.0.2</AssemblyVersion>
+    <FileVersion>4.1.0.2</FileVersion>
     <IsPackable>false</IsPackable>
     <IsPublishable>true</IsPublishable>
     <RuntimeIdentifier>win-x64</RuntimeIdentifier>
diff --git a/FModel/MainWindow.xaml.cs b/FModel/MainWindow.xaml.cs
index 00144f4f..9df6d8db 100644
--- a/FModel/MainWindow.xaml.cs
+++ b/FModel/MainWindow.xaml.cs
@@ -87,7 +87,7 @@ namespace FModel
 
         private void OnWindowKeyDown(object sender, KeyEventArgs e)
         {
-            if (e.OriginalSource is TextArea or TextBox)
+            if (e.OriginalSource is TextBox)
                 return;
 
             if (_threadWorkerView.CanBeCanceled && e.Key == Key.Escape)
diff --git a/FModel/ViewModels/ModelViewerViewModel.cs b/FModel/ViewModels/ModelViewerViewModel.cs
index 34b8cbbe..40dbce11 100644
--- a/FModel/ViewModels/ModelViewerViewModel.cs
+++ b/FModel/ViewModels/ModelViewerViewModel.cs
@@ -140,6 +140,7 @@ namespace FModel.ViewModels
                 }
             });
 
+            if (AppendMode && CanAppend) return;
             SelectedModel = p;
             Cam.UpDirection = new Vector3D(0, 1, 0);
             Cam.Position = p.Position;
diff --git a/FModel/Views/ModelViewer.xaml b/FModel/Views/ModelViewer.xaml
index e27aa15c..b0112861 100644
--- a/FModel/Views/ModelViewer.xaml
+++ b/FModel/Views/ModelViewer.xaml
@@ -44,7 +44,7 @@
                     </Grid.ColumnDefinitions>
 
                     <TextBlock Grid.Row="0" Grid.Column="0" Text="Models" VerticalAlignment="Center" Margin="0 0 0 10" />
-                    <ComboBox Grid.Row="0" Grid.Column="2" Style="{StaticResource ModelsComboBox}" />
+                    <ComboBox Grid.Row="0" Grid.Column="2" Style="{StaticResource ModelsComboBox}" IsEnabled="{Binding IsReady}" />
 
                     <TextBlock Grid.Row="1" Grid.Column="0" Text="Triangles" VerticalAlignment="Center" Margin="0 0 0 10" />
                     <TextBlock Grid.Row="1" Grid.Column="2" Text="{Binding ModelViewer.SelectedModel.TriangleCount, FallbackValue=0, StringFormat={}{0:### ### ### ###}}" VerticalAlignment="Center" HorizontalAlignment="Right" />
@@ -64,20 +64,21 @@
                             <ColumnDefinition Width="*" />
                         </Grid.ColumnDefinitions>
 
-                        <Button Grid.Row="0" Grid.Column="0" Content="Focus" Click="OnFocusClick" />
-                        <ToggleButton Grid.Row="0" Grid.Column="2" IsChecked="{Binding ModelViewer.AppendMode}" Style="{DynamicResource {x:Static adonisUi:Styles.ToolbarToggleButton}}">
+                        <Button Grid.Row="0" Grid.Column="0" Content="Focus" Click="OnFocusClick" IsEnabled="{Binding IsReady}" />
+                        <ToggleButton Grid.Row="0" Grid.Column="2" IsChecked="{Binding ModelViewer.AppendMode}" IsEnabled="{Binding IsReady}"
+                                      Style="{DynamicResource {x:Static adonisUi:Styles.ToolbarToggleButton}}">
                             <TextBlock Text="{Binding IsChecked, Converter={x:Static converters:BoolToToggleConverter.Instance},
                                     StringFormat={}Append {0}, RelativeSource={RelativeSource Mode=FindAncestor, AncestorType={x:Type ToggleButton}}}" />
                         </ToggleButton>
 
-                        <Button Grid.Row="2" Grid.Column="0" Grid.ColumnSpan="3" Click="Save"
+                        <Button Grid.Row="2" Grid.Column="0" Grid.ColumnSpan="3" Click="Save" IsEnabled="{Binding IsReady}"
                                 Style="{DynamicResource {x:Static adonisUi:Styles.AccentButton}}">
                             <TextBlock Text="{Binding ModelViewer.LoadedModelsView.Count, StringFormat={}Save All Loaded Models ({0})}" />
                         </Button>
                     </Grid>
                 </Grid>
                 <Separator DockPanel.Dock="Top" Tag="MATERIALS" Style="{StaticResource CustomSeparator}" />
-                <ListBox x:Name="MaterialsListName" DockPanel.Dock="Top" Style="{StaticResource MaterialsListBox}">
+                <ListBox x:Name="MaterialsListName" DockPanel.Dock="Top" Style="{StaticResource MaterialsListBox}" IsEnabled="{Binding IsReady}">
                     <ListBox.ContextMenu>
                         <ContextMenu DataContext="{Binding PlacementTarget, RelativeSource={RelativeSource Self}}">
                             <MenuItem Header="Copy Name" Click="OnCopyClick">