Is it possible that you upgrade to the latest version of RadEditor, as much of the bugs (I believe you are encountering them with IE6) are fixed. Still, there are bugs, though, as all of the dialogs of RadEditor are undergoing serious front-end redesign, but they will be fixed with the release of Q3.2008. That particular dialog, TableWizard is already fixed, and it looks better than ever!
All the best,
the Telerik team
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