Thank you for the clarification. We managed to set up your case and to reproduce the issue.
The Docking control is using a big transparent window to host its ToolWindows and compasses. This is causing the Terminal Service to consider it as a fullscreen application and that is causing the bad behavior. Unfortunately we don't have a work-around for this problem.
We are considering a change in the way RadDocking works and removing this Window as it is causing some other issues as well. But I can't tell you a specific date RadDock will be reworked. The most optimistic date is Q1.
Sorry for the inconvenience caused. Let me know if you have further questions.
the Telerik team
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