Yes, the arcaves map is modded. It has new items and different puzzles inside. However, using the old map won't really make a difference to the game in the long run. No new global variables are set there, so you will be ok. The game will resume in the rest of its modded form when you return to the village. However, I am concerned. If you did all those and are still having this problem, I am afraid you will have this issue on some other map you enter not too far into the game. I hope I'm wrong and that everything still works for you. All the steps you did are typically what people have done to get this working when they have problems with it. Just to make certain, though: you don't have a patch000.dat file, do you? Also, before you started playing, did you set the files in the proto/critters and proto/items to read only?