Visible crew/equipment: When Zaphod says his first line "I certainly didn't survive.", you can see the person who plays his third arm standing behind him.
The Hit Car - S1-E3
Continuity mistake: When Ralph catches the guy in the van Bill pulls his car up alongside, and when Bill gets out of the car he has a blood stained gauze bandage around his left hand, but as Bill cuffs the guy in the closeup the gauze bandage has vanished. (00:28:20)