Is there a way to view a backup (perhaps stored in a mounted full system backup image) with a regedit type program so as to export from a backed up key to a .reg file as you can do with regedit? A utility to convert a backup to a .reg file would probably do the trick because I'm pretty sure there are regedit type utilities that can operate on .reg files.
My system path was destroyed by something I installed and I didn't discover that for a few days during which the registry had evolved some. I don't want to restore a whole registry backup, just retrieve "HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\Environment" entry from the backup to a .reg file for restoration to the regstry.
In many, if not most, cases a full registry restore to some past state is far too drastic.
Thanks