I am glad to hear you have successfully resolved your difficulty.
If you believe the issue with the modal overlay stems from our code and not from a global CSS rule that changes some property pleas share some more details on the issue you are having - the desired and actual effect, as well as the circumstances that lead to it - is it browser specific, what is the exact setup, etc. I am asking this because I have not seen erroneous behavior with the modal overlay and if there is indeed some scenario that does not work well we may need to address it. If it indeed bug in the control we will gladly reward your efforts with some telerik points.
the Telerik team
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