I followed the described by you scenario (using the 2012.1.215.40 version of the controls) but I still not able to reproduce the issue on my side. I have tested it in Mozilla and IE9 but in both of these browsers the control behaves properly. For your convenience I have recorded my tests - could you watch them and see if I am missing anything - FF
Regarding the online demos - this actually is the expected behavior of the control. The sizes displayed at the bottom of the control show the real width and height of the loaded image. These values would be changed only if you save the image after the resize, but not only the crop operation itself.
Nevertheless, since the problem is not reproducible on our online demos (which are running the latest version of the controls) we recommend you to upgrade to the latest 2012 Q3 build of RadControls for ASP.NET AJAX.
the Telerik team
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