I have had Yeslick go funny, repeatedly dropping out of the party and rejoining, not allowing us to do anything else between the drops and rejoins. This was in the Cloakwood mine...tons of crud around the hobgoblin floor that we didn't pick up. I assume this had something to do with his quest, but it persisted even after he personally scragged Davaoern. Should I hand him the key? Or send him naked against a mustard ooze to get rid of him? This behavior persisted in several saves I had of various times. I can pause the system and send him elsewhere away from the party and things are OK as long as he can't talk to us.

I don;t know how to fix it as such but all i can do is classify that it is a bug and PROBALy couldn;t be cured by giving the key etc, just sit around a expert will come along soon.

Try getting the newest patch. It might help you with the bugs. Make sure to read the readme file that comes with it. If you still have problems you can always ask the guys over at bioware about it and see what they have to tell you.