While the CV viewer doesn't appear to be available to download anymore, there are samples available in your account to view RadNavigation in action. Sign into your account into the downloads section, under Silverlight you'll see Navigation Examples. This contains the Books, Cars, and Wizard example projects with full source code. CV viewed might be gone because there is no longer a default SlideTransition interface in RadNavigation...
But fear not!
Thanks to Boryana, we do have an example of how to use iTransition to recreate the SlideTransition effect. You can download that here:
Those two combined should get you started on recreating the effects in CV Viewer.