There's a Utility InCtr-5 [ In Control ] from Pc Mag which one can run before installing any program and again after install is done [ even after a reboot ] and which give a log of what the changes were made to the Registry.

The only problem is the is log is Megabyte size file to peruse !

Pc mag Uty's are no longer free . They charge $5.00 for any three. I have this one , but do not know how to send it ? If any body needs it to try .

Please leave a clear instruction . Thank you.