In the attached gif, the buttons inside the RadWindow are custom one which comes from the DialogView class. Correct me if I am wrong. As these buttons are custom, I have only tested the "x" button in the top right corner. When the button is clicked, the window is closed. You can find the sample project attached here. May I ask you to take a look at this project and let me know what else I am missing from your implementation to reproduce this. If it is will be easier for you, you can modify the project and send it back to me.
Regards,
Dinko
Progress Telerik
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