Note that all UI controls safe controls in the whole Windows Forms platform (not just Telerik controls, but all controls out there). Here is an article on MSDN, describing how to make thread-safe Winforms UI application. This means that any control from the Telerik UI for WinForms suite safe as well and cannot be used outside the main UI thread. You should use an Invoke to update the controls in threading scenario.
I hope this information helps. Should you have further questions I would be glad to help.
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