I tested the same scenario with the mentioned version of the controls - the designer worked as expected. You might also try to restart the VisualStudio after cleaning the solution and deleting the folders. If you have applied any custom Styles you can to remove them and see if this helps. However if still have the same you can open a support and provide a sample project demonstrating the issue, we will be glad to investigate it on our side.
If you have any other questions let us know.
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