So, you are getting this error too?  Here is the fix:

1. Uninstall Guidance Automation Extensions if you have them already installed (note that you will have to uninstall everything that depends on it too)
2. Open Cmd.exe as an administrator (find it in the start menu, right-click on it and choose "Run as Administrator")
3. enter msiexec /u guidanceautomationextensions.msi
4. enter misexec /i guidanceautomationtoolkit.msi (next install all software factories again)
5. Congratulations, no more error

I found this out the hard way.  When will I learn to ALWAYS do installs on vista as an administrator?