Thank you for the keen interest in our controls and all your feedback! It's truly rewarding to know that people are excited by what we're working on here at Telerik!
OK, now to the point:
"would it be possible to give it a bit of animation
Currently there is a number of limitations in the framework that prevent us from adding nice custom animations to RadControls for Silverlight, but you can rest assured that we're working on that issue. You will see custom animations added to most of our controls in one of our next builds.
"Blend can not show the inner levels of the panel
We are aware of this limitation and it will be resolved in our next build by displaying dummy items when an empty RadPanelBar is dragged on the design surface of Blend.
"I get tons of errors related to COM
We investigated this problem and discovered that it is caused by Blend calling some core methods of the control in an incorrect sequence, thus triggering inner exceptions. However, this behavior affects only the design-time experience in Blend and does not occur when you run your application. The issue will be resolved in our next build.
As for your last comment about the missing options when using gradient backgrounds - this must be caused by the COM errors you get. I tried to reproduce your case using an internal build of the control that contained a prototype of the solution of the COM errors and didn't see any options missing. So, I believe these issues will be resolved by the COM errors fix as well.
the Telerik team
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