Factual error: Kryten tells everyone that the matter paddle transmits matter in digital form from one place to another at the speed of light - he is very clear on this point. He then locates Waxworld, which is 200,000 light years away. Okay - so when they use the matter paddle to transmit themselves to Waxworld, why doesn't it take them 200,000 years to get there?
Continuity mistake: When the crew are wheeling the Cat in the corridors of Red Dwarf, Kryten is holding onto the Cat's hand. In the next shot he is pushing the stretcher. (00:23:00)
Continuity mistake: When Lister drops the magazine in front of Rimmer it lands closed. When Rimmer begins to read it, it is open on the floor. (00:13:25)
Continuity mistake: When Kryten decides to be a mechanoid again, Lister gets up and grabs his jacket and swings it around his shoulders. The camera cuts to Kryten for a second then back to Lister, who now has his jacket on fully. The amount of time the camera was away from Lister would make this impossible for him to put the jacket on that quickly. (00:22:15)
Continuity mistake: In the scene where Lister is talking to human Kryten, just before Lister sees the photos, keep an eye on Lister's hat. It is perched on top of his head with about an inch of hair showing, yet the next shot shows the hat covering all of the hair, then it goes back to an inch of hair showing again. There is no time for Lister to have adjusted his hat between cuts. It is clear the line had to be re-shot. (00:12:35)
Factual error: The justice computer states that Rimmer is guilty of 1167 counts of 2nd degree murder, each carrying a sentence of 8 years giving a total of 9328 years. This is equivalent to 1166 counts. (00:14:00)
Revealing mistake: Rimmer is able to move the swivel chair in this episode despite being a hologram. (00:24:35)
White Hole - S4-E4
Continuity mistake: Just after Kryten says what point in time he would like to return to, he is looking down and working with the screwdriver. The camera angle changes and he is looking straight forwards with the screwdriver on its side. (00:05:35)
Continuity mistake: Kryten has three spare heads but in 'The Last Day' in series 3, he only packed away one head. (00:18:40)
Visible crew/equipment: When the crew are standing before the Judgement computer (when Lister is worrying that he will be sent to prison) if you look above Lister's head you can see a microphone bob up and down into shot. (00:11:10)
Suggested correction: Kryten says that the paddle sends them via subspace, so they will reach it almost instantaneously (rewatch the scene, he never says they'll travel at lightspeed).