Don't you get experience when you leave Altofix's house, rather than talking to the chieftain's son?
With the group of imps, there should be a cut scene with the imp hero, after you give him the spider leg he asks for in the spider forest. If there is a problem after he starts talking, some people have avoided it by exiting the conversation rather than talk to him. Another workaround is to try leaving one character on the other side of town, and approach the area with a single character.
