I already answered to your post in the other thread
on the subject. For convenience I will paste my answer here as well.
At present, we do not provide Script# ImportLibrary for RadControls for ASP.NET AJAX because it was not wildly requested by our clients. I have logged this into our PITS and if reasonable amount of users vote for it we will consider adding such resource with the controls distributions. Here you can find the PITS Issue: Public URL.
On a side note, if you are willing to created and maintain Script# ImportLibrary for RadControls and post it as a CodeLibrary you will compensated either with Telerik points or other way.
All the best,
the Telerik team
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