Well, I tried this mod last night. I had some trouble starting up Gothic 2 because it doesn't mix well with Windows 7 64bit.
There are some servers out there, 3 of them had people on it. All of them were polish (I think), so it was hard to make sense of what was going one.
There was an RP server which seemed like a fun idea, especially considering that the population limit was like 140. However there were only five players online, me included. They also didn't speak english, so whatever RP-ing there was I couldn't take part off. Still, it was fun to use the /pee animation near people or from the top of buildings. Oh, it was set in Khorinis.
The other server I joined had 15 people online and was set in the Colony from Gothic 1. The gamemode was some kind of Deathmatch taking place in the Old Camp. I must say, it really had the feeling and atmosphere of the first two games. You could choose between the 3 camps and pick a class which corresponded to the main NPCs.
As a side note, this modification allows the players to customize their character to some extent. One can customize the head model, the head texture, the body texture and the walking animation.
I'm sure that if the game had a bigger community, this mod would become even more fun.