There have been a number of people on IRC complaining that the RC is not working, and they are unable to revert back to an older version even after uninstalling the RC. The installer for the older version states that a newer version is still installed.
The solution for this is to first uninstall all other Windows Live programs. Next, download
Windows Installer Cleanup and remove all Windows Live components that appear on the list.
This should now allow any other Windows Live version to be installed.