Continuity mistake: When Lister and the Cat first see Lisa Yates on the screen, their shoulders are together. In the next shot there is a wide gap between them. (00:18:30)
Continuity mistake: In 'Thanks For The Memory', both Lister and The Cat injure their left feet when they drop the gravestone; but The Cat is seen to be wearing a plaster cast on his RIGHT foot. (00:12:10 - 00:27:00)
Continuity mistake: When Lister and the Cat are on the moon, their casts keep appearing then disappearing. (00:15:15)
Continuity mistake: When Rimmer is talking about Lisa Yates to Lister, his tie is undone. When it cuts to the black box camera, his tie is correctly tied. (00:22:10)
Continuity mistake: Just before Lister says 'I'm going to give him Lisa Yates' he is looking forwards. When the camera angle changes he is looking at the Cat. (00:18:15)
Continuity mistake: When Rimmer falls asleep whilst Lister is doing the jigsaw, there is a whisky bottle on the table. Later in the episode, when being viewed on the black box, the whiskey bottle is no longer on the table. Lister could not have thrown it away since he left the table to the Hologram Simulation Suite at The End of the scene. (00:10:20 - 00:19:35)
Continuity mistake: When Lister is doing the jigsaw and Rimmer starts singing in bed, the pint mug on the table has nothing in it. Later on, when Lister returns after giving Rimmer his memory, an inch of whisky has suddenly appeared in the bottom of the mug. (00:10:20 - 00:19:35)
Continuity mistake: When Rimmer is talking about Yvonne McGruder, Lister is not wearing a hat. When we see the black box recording of the conversation, Lister is now wearing one. (00:08:25 - 00:16:45)
Continuity mistake: When Rimmer is about to tell Lister how many times he made love, Lister tells him that he'll "wake up in the morning with a hangover." But Rimmer and Lister already have fallen asleep and woken up, and they have the hangovers right now.
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.