You have the following scenario:

The UpdateValueEvent property is set to "LostFocus". You have bound the Value property of the control to a property from your ViewModel. 


When this property is changed programmatically from negative to positive several times, the Value property of the control isn't updated correctly.

It stays negative when it must stay positive.


Workaround (if applicable):
You can change the UpdateValueEvent property to "PropertyChanged" 

Other Possible workaround (if the bound property is named "Sum")

private void radMaskedNumericInputSum_ValueChanging_1(object sender, Telerik.Windows.Controls.MaskedInput.RadMaskedInputValueChangingEventArgs e)
{
    if (this.Sum != (double)e.NewValue)
    {              
        e.Handled = true;
    }
}

Dialog for inputting the password should be implemented in order to be able to decrypt the file content.

Currently large diagrams are hard to export with good quality because of the memory limitation in WritableBitmap when the DPI is increased.

 -- One option is to use BitMapCacheBrush (discussed here http://www.telerik.com/forums/low-resolution-using-exporttoimage-on-big-diagram)

 -- Another option is to export multiple images of the diagram which cover it all. Then possibly combine these pictures into one.

 -- Also , you can try increasing the operating memory of your Visual Studio

I really liked this feature and noticed you implemented it for WinForms already: TextBox Improvements in Telerik UI for WinForms

Would be great to have it for WPF as well!

Add a control that allows you to define a number of steps. Each step should be displayed with some kind of visual (like an ellipse for example) and each visual should be connected with a line. The line could be animated to look like a progress bar.

This kind of visualization is found in the Multi-Step Form feature of Kendo UI for Angular.

In the meantime, you can achieve this effect by implementing a custom control as shown in the First Look demo of RadButtons.

The drop-down menu does not close when a context menu is opened on top of it, even if the KeepDropDownOpen="False". The control would need to move the focus in order for the drop-down to close.

To work this around, you can use the CloseDropDown() method of the MultiColumnComboBox control.

Add a ScrollViewer to the PanelBarItem ControlTemplate

add a textbox which allows users to find matching distinc values when using report filters. Very valuable if you are dealing with many distinct values. 

The issue is observed when the added table is preceded by a paragraph with a font size different from the default one. As the issue is caused by a broken mouse capture, the following workaround can be employed:

someRandomFrameworkElement.CaptureMouse();

someRandomFrameworkElement.ReleaseMouseCapture();

When a whole paragraph is selected and the Set Numbering Value command is executed, the numbering value of the next paragraph is changed instead of the current one.

private void radRichTextBox_CommandExecuting(object sender, CommandExecutingEventArgs e)
{
    if (e.Command is ShowSetNumberingValueDialogCommand)
    {
        this.radRichTextBox.Document.CaretPosition.MoveToPosition(this.radRichTextBox.Document.Selection.Ranges.First.StartPosition);
    }
}

An exception is thrown when the ShowNetworkLocations property is set to false.

System.ArgumentNullException: Value cannot be null. (Parameter 'value')
   at System.String.StartsWith(String value)
   at Telerik.Windows.Controls.FileDialogs.Helpers.PathHelper.CapitalizeNetworkPath(String path)
   at Telerik.Windows.Controls.FileDialogs.ExplorerControl.BringItemIntoView(DirectoryBaseWrapper itemToBring)
   at Telerik.Windows.Controls.FileDialogs.ExplorerControl.BringCurrentDirIntoView()
   at Telerik.Windows.Controls.FileDialogs.ExplorerControl.MainNavigationPaneLoaded(Object sender, RoutedEventArgs e)