Continuity mistake: The Cat brings down the town sign by shooting the right hand side of it. Seconds later, when they pick Kryten up, the sign is hanging in front of the Livery building, which would only have been possible if he'd shot the left hand side.
Revealing mistake: At the start of the episode, we see Lister in black and white talking to Loretta. Then we cut back to what's really happening, he is playing on the AR console. Look at the door behind him, you can see Kryten's hand sticking out in the doorway. He is supposed to rush in and start talking, but you can see him waiting off camera to be told when to enter the room.