Basically, no visual elements should be cut off. Based on the supplied information, it is hard to pinpoint the cause of the problem. To do so, it will be best if you open a formal support ticket, and send us a small working project, demonstrating the visual glitch, for additional review and testing.
All the best,
the Telerik team
Q2’11 SP1 of RadControls for WinForms is available for download (see what's new); also available is the Q3'11 Roadmap for Telerik Windows Forms controls.