RadCarousel uses PointAnimationUsingPath in WPF that allows the user to draw any shape and make the items flow in circle or whatever shape the path has drawn. This is not available in Silverlight though so we could not prot the RadCarousel for Silverlight so easily and implemented a RadCoverflow.
RadCoverflow does not support the circular rotation.
I am sorry for the inconvenience.
the Telerik team
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