I finished the orc fortress (ie killed Kessa, and then escaped up past the gnolls), but I can't seem to progress the game after that. The giant fortress has a magical barrier, and the wizard tells me I should complete other quests first. However, I can't figure out anything I can still complete. The mountain fortress is sealed with a door I can't open, and I can't find anything additional to do in the orc fortress.
Please let me know if my games bugged or whether there is something I can do.