As replied in your support ticket:
"Thank you for contacting us and reporting the issue you have come across. I am happy to say that our development team found a solution. We plan to introduce it with the upcoming AppBuilder 2.11 release, next week. However, if you wish, you can apply the necessary changes on your side manually in order to fix the AppBuilder extension in Visual Studio 2015. Here are the steps, you will need to perform:
1. Close any opened Visual Studio instances.
2. In File Explorer, locate the folder of the AppBuilder extension for Visual Studio 2015. Normally, the path should be something like: %localappdata%\Microsoft\VisualStudio\14.0\Extensions\hoq0t24t.vb5\
. The folder in yellow (hoq0t24t.vb5
) is different each time and you will have to search for the one that contains the AppBuilder extension on your computer (search for Telerik.BlackDragon files).
3. Once in that folder, you have to delete the following file: Microsoft.Windows.Design.Host.dll
4. Open Visual Studio 2015 and see if AppBuilder will load as expected.
If the above doesn't help, please re-install the AppBuilder Extension for Visual Studio and go through the steps again."