We are not aware of such a change and issue. I tried your scenario and things seem to be working fine with me: http://screencast.com/t/tI9wknA035
. I am also attaching my test page here as reference. What I can currently suggest is that you remove the center() call and instead of all this logic you can call radopen() as it will show a RadWindow even it one with the provided name is not declared:
oWnd = radopen(url, windowname);
Try these and see if it helps. If not - I advise that you open a formal support ticket and send us a simple, runnable project that shows this behavior so we can investigate it further.
All the best,
the Telerik team
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