Hi,
can i still patch a game, when the GOG Offline patch.exe doesn't find it's location? Maybe with command line parameters, manuallly unpacking the update or whatever?

{Why I'm asking:
- My SSD died and went read-only, so I copied games and savegames to a backup HDD.
- Installed Windows 10 on the replacement SSD and put games/Saves back in place.
- Cyberpunk 2077 v1.22 runs fine that way, but:
- Patches I collected over the months do not, can't find the game.
- Not sure if v.1.3 likes my v1.22 saves when I leave out v1.23
- Also seems like a huge waste of traffic to just reinstall v1.3 completely
}

A complete re-install would probably still be more straightforward, not to mention saving you the time you'd potentially waste on unpacking the patch installer(s) as well as the game archives, manually checking and replacing files, pack it all up again and in the end, have it go entirely kaputt on you after all, because you missed a file, checksums don't match up anymore or something along those lines.
Strange that the patch installer wouldn't track down the install directory (which they are pretty good at usually), that's a new one, to me at least.

Old saves are upwards compatible and should work with any newer patch versions, by the way.

It's looking in the registry. Since he literally packed the files and moved them, reinstalled windows then put them back, he has no registry entries pointing at the game install folders. One of the little caveats to just copying files. DRM-free doesn't necessarily mean portable. If you're not against using Galaxy, you can have Galaxy Scan and repair the installation, including adding in the registry entries for the game. Rollback to the patch of your choice if you don't want it to update completely to the newest version, and then uninstall galaxy, should you not want to use it. If you're completely against using Galaxy even to update the game properly, then you'll probably have to redownload the game, that is, if you don't have your original installers.

Thank you both!
I tried the GOG Galaxy repair function, but this doesn't seem to add the needed registry entries until afte downloading all the missing updates, if it does.
So I ended up renstalling via newly donwloaded v1.3 Offline installer, the old saves work fine.