We are sorry to hear that you experience problems with our controls.
We have a known issue with the CTP edition of our RadGridView. When you show a grid that has not been bound to any data at that time, an exception will appear. This bug has already been fixed with the latest SP2 release, which you can download from your account.
Also, you can work the issue around by binding the RadGridView control to an empty list. For example:
|this.testGrid.ItemsSource = new List<string>();
As for the documentation glithces - we are continuously working on the matter. With the latest SP2 release we have added a full documentation for the RadNavigation control. We will be improving the rest of the topics so that the help becomes more consistent and helpful. We apologize for the inconvenience this lack of documentation causes you. You can always write to us when a certain problem appears to be a show-stopper for your development and you cannot find enough details within the support resources (docs, kb articles, etc.).
the Telerik team
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