Npc's fail to load while running dialogue.

Had it happen in Demands of the Qun, after lighting the signal fire Gatt was completely invisible and his dialogue didn't show. Bull just talked at thin air throughout the entire sequence.

For Sera's quest where you encounter the ambushing noble, I kill the thugs, get the dialogue from the noble trying to calm me down, but he is nowhere to be found and I can't continue the dialogue.