Plot hole: At The End, Kryten, Rimmer and Lister are in a lift facing off six gelf shapeshifters - two copies of each real person, in a Mexican standoff. Nobody knows who to shoot, as they might shoot the real person instead of the shapeshifter. But the real people know they're real - all Lister has to do is shoot the two fake Listers, Rimmer shoots the fake Rimmers and Kryten shoots the two fake Krytens, problem solved. Not to mention Lister is now a soulless, unfeeling killing machine. Earlier he shot and killed a shapeshifter who could well have been Cat - he didn't know it was a shapeshifter and by his own admission he didn't care. We have already seen how fast on the draw he is - why didn't he just open fire on the six shapeshifters, Kryten and Rimmer in order to ensure his own survival?
Suggested correction: The point of a Mexican standoff is no one is in a position to shoot first for fear of being shot themselves. We're told the shapeshifters have no problem killing each other, so as soon as the real person starts to shoot, everyone may start firing, which could result in a real person being killed. Additionally, the only time all 9 are pointing guns at each other is in the lift. Before that, it's 3 groups of Listers, Krytens, and Rimmers, so no one is facing off with their shapeshifters. The only safe way to shoot the 6 shapeshifters would be to do it at the same time, and there's no way Lister, Kryten, and Rimmer could coordinate that. And, like all Mexican standoffs, it can only be resolved from outside help.
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?
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).
Revealing mistake: At the start in the cockpit of Starbug, the green screen behind Lister is visible instead of the painted starfield that should be there. (00:02:35)
Suggested correction: That is because Starbug is parked inside Red Dwarf at the time, and the stars wouldn't be visible.
Continuity mistake: Just after The Inquisitor is frozen when Lister and Kryten switch gauntlets, the glove gets onto Kryten's hand in one camera cut. (00:24:30)
Suggested correction: He's holding the gauntlet in his hand, but the angle of the camera makes it appear that he's wearing it.
Continuity mistake: In the forest, Lister and the Cat take a poster off a tree. They then show it to the man who gives them a lift. The poster is different to the one in the forest. (00:16:05)
Suggested correction: If you look at 00:13:47, you'll see that the closest tree has an odd poster. The other trees have the poster that they showed to the man that gives them a lift.
Emohawk - Polymorph II - S6-E4
Revealing mistake: Both Ace and the Emohawk get sprayed with the liquid Dyllinium, yet only the Emohawk becomes paralysed. (00:26:55)
Suggested correction: Ace is a hologram. Even though he is hard light, he cannot be harmed. Which is why he was able to jump on the grenade and not be harmed. So the gas spray wouldn't have harmed him either.
Continuity mistake: When the Cat picks up the golf clubs, his hair is sitting on his left shoulder. In the next shot it is behind his back. (00:10:40)
Suggested correction: His hair moved to his left shoulder when he turned his head and picked up the clubs, but you can see his hair go back behind him when he straightens his head.
Revealing mistake: When Baxter puts the Cat's head in the drinks machine and says hot bovrill, Kryten can be seen mouthing the line behind him. (00:22:20)
Suggested correction: Kryten is not mouthing the line "Hot bovril." He is just moving his mouth slightly up and down, which coincidentally happened to occur when Baxter was saying the line.
Revealing mistake: In the sleeping quarters, Rimmer turns on a swivel chair. This would be impossible as he is a hologram. 3.10. (00:03:10)
Suggested correction: As a hologram, this would also mean Rimmer could not touch or sit on the chair. The chair was likely a hologram as well, used to be operable by Rimmer. It has been shown before that Rimmer can still interact with other holographic objects.
Revealing mistake: When Lister is in jail with the Cat, as he is looking out of the window, he is naming famous people. He says "Mussolini" before he actually looks at him. (00:10:55)
Suggested correction: First, Lister is shown looking out the window throughout the scene, and second, he still has an entire view of outside the window within his eyesight. Lister likely already seen Mussolini within his eyesight before turning to face his direction, which he likely did to assure himself it was definitely Mussolini.
Visible crew/equipment: When the Cat says "You mean to help you get out if the program freezes" on Blue Midget, a soundman can be seen crouching behind the control panel. The top of his head is visible in the top right of the screen. (00:14:10)
Suggested correction: That is not the head of a soundman crouching behind the control panel, or any crew member for that matter. What you are seeing is Kryten's hand moving around.
Continuity mistake: From the model shot of Blue Midget, Kryten is seen sitting on the right. When the camera cuts inside the ship, he is sitting on the left. (00:22:40)
Suggested correction: When the exterior shot of Blue Midget is shown, it is not very easy to tell the crew apart. They appear blurred, so it is impossible to determine who is sitting in which place.
Other mistake: When Lister inadvertently sets off the Auto Destruct sequence, the computer voice says the ship will detonate in 15 minutes. The computer then says "the ship will detonate" every five seconds followed by how much time until detonation, but the time in which the computer says this is inconsistent. Two seconds after the computer says 15 minutes, the computer says the ship will detonate in 14 minutes 55 seconds. Ten seconds after saying that, the computer says the ship will detonate in 14 minutes 50 seconds. (00:01:50)
Other mistake: Cassandra says that all the canaries will be dead in 1 hour, with the exception of Rimmer, Kryten, Lister, Cat and Kochanski. However, Kill Crazy was still knocked out in the transport vehicle and presumably would have survived too.
Suggested correction: But Cassandra was known to lie if it suited her purpose, she said that Lister would harpoon Arnold through the head and kill him but that's not what really happened either.
Yes, Cassandra lied about Lister shooting Arnold through the head with a harpoon, but that was an attempt to stop Lister from killing her. Mentioning which of the canaries will survive had no impact on any of her plans, so not mentioning Kill Crazy survived is still incorrect on her behalf.
Revealing mistake: After Starbug has left Red Dwarf, the scene cuts to inside the ship where Rimmer tells Kryten to autopilot, and the background of space is entirely still, even though the ship is moving. (00:04:45)
Suggested correction: Stars are so far away that they do not appear to move when travelling in space, unless you reach incredibly high speeds or change direction.
Other mistake: An option for the new computer is breast size. A meaningless addition, since the computer is just a head. (00:07:35)
Suggested correction: When setting up the computer, there is an option for frame size. Kryten chooses close up, and when Pree appears on-screen Rimmer reacts to the fact that her breasts aren't visible whilst Kryten says that he likes that frame size. Presumably, there were other frame sizes available that would reveal more of Pree's body, giving meaning to the option.
Suggested correction: Lister can only see M-Corp products and M-Corp employees. Cat is not an employee of JMC or M-Corp, so he disappears. Lister is the only member of the crew who is employed by M-Corp at this point.
Suggested correction: Cat was a descendant of the cat Lister brought aboard Red Dwarf. Would it be possible that the new owners might have stricter security controls, and Lister was sent to Stasis for a different reason?
Andy Benham ★
Inventing Deux ex machina explanations for a plot hole doesn't make it any less of a plot hole. M-Corp erases all of the Jupiter Mining Corporation's equipment, personnel and infrastructure from Lister's life. In no way is Cat a part of that. He has no connection at all to the Jupiter Mining Corporation, and until he meets him in Episode 1 no connection to Lister, either.
If M-Corp only erased JMC equipment from Lister's life, then Kryten, who belongs to DivaDroid and not the JMC, wouldn't have disappeared either. He disappears as he doesn't belong to M-Corp, not because he belongs to the JMC. Cat has no connection to M-Corp, as he wasn't a part of the JMC (as you pointed out), and is therefore erased for Lister.