Unable to start debugging! The silverlight managed debugging package isn’t installed.
If you are facing this issue when you try to debug your Silverlight 2 Beta 2 application from Visual Studio 2008 just extract the silverlight_chainer.exe into a folder and run Silverlight.2.0_Developer.exe from the folder. You even don’t have to quick Visual Studio 2008 during the installation.
I was facing this issue in a little project I started to experience Silverlight 2. It is realted to my today’s great interest Scrum! Wait and see.