At the time of this writing Silverlight Spy is in beta stage. We are always testing the tool and would love to have your feedback. In order to get the most out of it an installed package is required.
Download the compiled Win64 dll of Silverlight Spy 2.0.2 from our Forum. 
Click Start, then Run. Type in regedit  and follow the onscreen instructions.
Navigate to the following key 6add127376 otskjaed