Hello Josh Randal,
The lag in RadForm is most probably caused by problems in painting. We are working on various improvements in RadForm, including this, as we speak. Some of the improvements will be available in SP1 release, expected in mid April.
In the meanwhile you can try working around this issues by using ShapedForm and RadTitleBar.
Let me know if you need more info about this.
All the best,
the Telerik team
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