Continuity mistake: In the scene where Rube shakes hands with the animal protesters, he is not wearing the trash bag while shaking their hands. He is wearing the trash bag immediately before and after.
Plot hole: People who do not have their souls retrieved, before they are killed, will suffer the effects of the death on their soul, eg. the autopsied man has scars and cuts on his soul. So how come the woman who was crushed by a piano (whose soul was only ever retrieved afterwards) is unharmed in soul form?
Factual error: Towards the end of the episode, Mason reads a report on Daisy's death indicating she died 13 December 1938 in Marietta Georgia of smoke inhalation. It apparently was common knowledge that Daisy died on the set of Gone with the Wind (supported in the Halloween episode by someone who knew her when she was alive). The filming of the big fire scene in GWTW was 10 December 1938 so the dates are pretty close. But these early parts of the production of GWTW (and I believe the rest of the movie as well) were filmed in Culver City, CA, not Marietta.
Visible crew/equipment: During George's funeral, the camera swings around to follow the employee from Happy Time (the guy who George gives files, minus the red ones, to) and as he crosses the room to the other side, you see a crew member holding a boom mic, who looks over a little startled and moves back out of view.
Continuity mistake: When Guggenheim is sitting on the bench after he dies, he reaches for the pink index card and his fingers pass through it. But then how did the index card get to the bench? He had it when the gas tank hit him, so it could make sense if he still had it "with" him, like his clothes, but if he can't touch it now, then it should have stayed with his body, inside the building.
Continuity mistake: Dolores walks to the computer and tells Georgia "Apparently Stinky5000 votes for 'Ferns and Flowers'." The first look we get at the screen shows the message "Could you tell us what the dog's name is?" and nothing else. The next two glimpses of the screen we get shows "You forgot to put detergent into the dishwasher" and nothing else. It's after the next cut that Dolores says Hungrygirl wants to know the dog's name. As Dolores walks away from the computer, we get a last look at the screen. You can see Stinky5000's message "I vote for "Ferns and Flowers'" appearing on the screen.