Bill the trader in Abbey has goofy dialogue options. To buy the armor for Marcus you have to decline on the offer. Plus it seems that player character has options meant as Bill's replies.
I've had similar problems as Archont has had but with RP1 and some other mods. They seem to be related with saving and loading your game while in combat. Gecko Jesuses (, or Jesi?,) and other resurrecting creatures were about. Weapons didn't do damage or use ammo at all.
However party...