Are you using Visual Studio 2010 together with Windows Phone Developer Tools CTP(WPDT CTP) to hack those Apps?
Thinking of upgrading to Visual Studio 2010 RTM that was released the 12:th of March?
If so you need to know that the RTM now released is not working with the Windows Phone Developer Tools CTP!
Microsoft is working on an update and estimate this will be done in a few weeks they say. If you want to get a notice when it’s ready you can visit register here.