Getting An Error IndexOutOfRangeException When Using Appstylist for ASP.Net

I get an error “IndexOutOfRangeException” when opening the standard wsl file called InfragisticStyleLibrary.wsl.
I used AppStylist for ASP.Net to open the file.
I tried uninstalling the software and reinstalling it, but the problem still persists.
Did anyone experience the same problem, and do you have a solution to this issue?
The attached image shows the exact error I received when opening the file.

Error:
Unhandled exception has occurred in your application. If you click Continue, the application will ignore this error and attempt to continue. If you click Quit, the application will close immediately.
Index was outside the bounds of the array.
