There is a technical problem with registering 3rd party binaries in the VS toolbox for WP7 specifically. This is the reason why this is not implemented in our installer. We are working with Microsoft in order to fix the issue.
Unfotunately It is unlikely that we will fix this for the Q2 release. Once we have more info - we will make sure to share it with you.
Thank you for your patience.
the Telerik team
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