Supporting the custom window that you implemented is beyond our support and we cannot provide you with a solution in this case. Please note that if you experience any problems with our controls, we will do our best to provide a solution as soon as possible.
As an alternative of the custom window I suggest you to use the RadWindow
control with applied customizations. You could fully customize the appearance of the window by implementing a custom skin
. Also you could add custom buttons to the title bar.
In this case you will be able to use the rich client-side API
of the control without any problems.
I hope this helps.
All the best,
the Telerik team