There was a patch that updated Dungeon Keeper 2 from 1.7 to 1.8. It's even still linked on the GOG wiki for the game:
http://www.gogwiki.com/wiki/Dungeon_Keeper_2#Unofficial_patches

Is it still useful for anything?
It claims to add these:

NOTE: Patch 1.7 must be installed for this update

CHANGELOG:
==========

- The game can now be played without the CD
- The movies can now be watched without the CD
- Fixed a problem with Safedisk
- Fixed a problem with QSound
- Fixed a problem in the chat-lobby, users with different language-versions of DK2 can
now chat with each other
- The official DK2-Editor is included
- The DK2-Bonuspacks 1,2 and 3 are included
- The maps 'Furnace' and 'Olympia' are now compatible to each player
- The maps 'Islands' and 'Platform' are available for skirmish
- The map 'Traptime' is available for multiplayer
- In some campaign-levels there couldn't attract Goblins, Fireflys. Rogues,
Black Knights and Dark Angels, now this creatures are available in all this levels
- The german version of DK2 is now uncensored (blood and torture animations)

I have tried installing it, but it still says 1.7 in the game menu. Not sure if it actually installed properly.
Anyone knows anything about this?
I know GOG did their own patching so I'm a bit curious....

Edit: I have replace the files from the 1.8 patch directory into the base directory, but it doesn't seem to work... hmm

you can find a full breakdown on which versions are good and which ones aren't: [url=https://keeperklan.com/threads/2957-Have-GOG-DKII-which-patches-would-work-best]https://keeperklan.com/threads/2957-Have-GOG-DKII-which-patches-would-work-best

You can find there you shouldn't use 1.8.

You can, however, take a look at the General Improvement Mod, which is based off version 1.51 (the last one to have proper AI): https://keeperklan.com/downloads.php?do=file&id=109