The Microsoft manifest file is an XML file that helps define the Window's platform's relations to the CRT (the display) and other programs (paricularly the runtime dlls msvcr80.dll, msvcp80.dll, and msvcm80.dll), and is part of the .Net framework. SL has a similar manifest file in its directory. I uninstalled .Net, but got a similar result - SL froze before fully opening the window. Vista doesn't live without .Net, so I had to go back to a restore point. I reinstalled using the release candidate, but did not see the same error, and the program still freezes.
I would like to be part of the SL community, but this is a technical problem that I can't resolve.