Reinstall 2 games :
Install Dom 2.02, patch to 2.06, copy the whole structure and your 2.06 game files to another, let's say "Dom2.06" folder.
Then upgrade to 2.08 the original install.
I did this when 2.06 went out to continue a game with people only having the demo, and had no problem.
Originally posted by Norfleet: If there are ANY 2.08 files within reading distance of the 2.06 executable, the game will barf: This includes, but is probably not limited to, the entire newlords directory: If you've created *ANY* 2.08 pretenders, they must be removed from the newlords directory before starting the 2.06 exe. So if you made a new pretender for your 2.08 game using the 2.08 executable, the 2.06 exe will try to read it and barf. Gotta remove the files.
I did exactly what you described and it works just fine for me. I have bunch of pretenders created with 2.08 and bunch of games played with 2.08 and I can still run 2.06 in the same directory and play MP games with it (haven't tried 2.06 SP though).