Thank you for the questions.
The videos you are referring to do not have any sound or dubbing - they just use text call-outs. We plan to update them soon.
I was not able to reproduce the behavior you experienced. I created a test project containing a UserControl and two custom themes and they were applied correctly to the UserControl's RadControls. I am attaching this project to demonstrate the normal behavior.
If your case is somehow different, please open a new support ticket and send me a sample project. This will allow me to address any potential issue and to give you more accurate assistance.
the Telerik team
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