When you log in our site and enter your client profile, you will see to the left a label called "My Licenses". Under it you will se another called "My Free Trials", which you can click and see links to the trial versions of all our products.
The exception you receive is a known issue, but fortunately there is a simple workaround. You need to reference the following four assemblies: Telerik.Windows.Data.dll, Telerik.Windows.Controls.dll, Telerik.Windows.Controls.Input.dll and Telerik.Windows.Controls.GridView.dll. Once you do that, the exception will no longer occur when you drag and drop a RadGridVIew control from the toolbox.
If you need any further directions, we'll be happy to assist you.
the Telerik team
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