I am getting an error installing the latest version. It seems that the first installation failed with an Add-In-manager error similar the the "80070002" experienced by someone else. Then I tried to reinstall the version and got a .Net Framework Installation Utility error with the following error

EventType : clr20r3     P1 : installutil.exe     P2 : 2.0.50727.1433    
P3 : 471ebfbb     P4 : mscorlib     P5 : 2.0.0.0     P6 : 471ebc5b     P7 : 1295
P8 : 14     P9 : system.io.filenotfoundexception 

Everthing is stuck now?

Michael,

If you don't find the fix to the problem, you may want to try Windows Restore to restore your registry state at a point you could try reinstalling SF again.  Not related to SF, I have seen this type of issues with Windows Updates which may corrupt the registry entries that may cause this kind of unknown errors, then after using Windows Restore you can go to Windows Update and reinstall whatever may be missing.

Keep in mind that Windows Restore may remove registry entries for any program installed in the period of the restore point and you may need to reinstall it.

Good luck!

Edhy Rijo