vrubayka: Risen 1
The latest update brought new bugs and broke mod support. On Steam, the original Risen 1 with mod support and less bugs can be played by choosing the "original" branch in the Steam preferences.
On GOG it's not possible. The original version of Risen 1 should be added as a goodie.
I asked GOG on Jan 26 to add offline installer for the original Risen under extras for the game, since the new one has issues and different system requirements, and got this reply on Feb 13:
"I will make sure to pass on your feedback to the appropriate department but, as of right now, the only way of going back to an older version of the game is to use GOG GALAXY."
They might do something about it sooner If more people ask them.