Hello Dave,
We managed to reproduce the problem.
There is some issues which creates problems when you insert rad window into a rad grid.
We added a description of the problem in our bug tracking system will provide a fix in one of the future releases.
As a workaround you can use an external aspx page.
Thank you for reporting this issue, your telerik points have been updated.
Best wishes,
Yassen
the Telerik team
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