We tried to reproduce the reported issue following your steps, but to no avail. Please refer to the attached movie for details.
I'm afraid we could not be of much help unless we reproduce the issue on our side. It will be best if you can open a support ticket and send us a simple running project (incl. your custom skin, CSS, images, DB backup if needed and so on) demonstrating the problem. In that way we can reproduce and pinpoint the problems you're facing on our side, understand the logic of your application and provide a solution.
All the best,
the Telerik team
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