Looking through your download history it looks like you have installed the main RadControls for ASP.NET AJAX installation package (used for ASP.NET development in Visual Studio), instead of the package containing our SharePoint web parts.
You should be using the "Sharepoint 2010 Web Parts" download from the RadControls download page:
Download RadControls for ASP.NET AJAX Version: 2012.2 912 (Sep 12, 2012)
Let me know if that helps.
the Telerik team
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