Continuity mistake: The sand that lands on Rimmer's shoulder when Lister and the Cat drive away on the bike disappears in the next shot. (00:18:10)
Timeslides - S3-E5
Continuity mistake: We are told that it is impossible to move outside the frame of a slide, yet when we are shown the slide of young Lister and his band, all we see is the band on stage but the crew move freely about the pub. (00:11:40)
Timeslides - S3-E5
Continuity mistake: When the slideshow starts, the photos in Lister's hands disappear between camera cuts. (00:06:20)
Continuity mistake: When the ducts are being backwashed, Lister's dreadlocks are on his right shoulder. But when the shot changes and he says "I hate this. I really hate this.", his locks are on his left shoulder. Then the shot changes again and they're back on his right shoulder. (00:23:53)
Terrorform - S5-E3
Continuity mistake: The cutting torch Kryten uses to cut his hand off appears from nowhere. (00:02:20)
Emohawk - Polymorph II - S6-E4
Visible crew/equipment: When Rimmer says 'details halibut breath' a boom mic can be seen to Rimmer's left. (00:07:30)
Quarantine - S5-E4
Revealing mistake: As pointed out by Danny John Jules on the DVD Commentary, during the 'Feckles, Heckles, Hackles, Schmeckles' argument, Cat pushes his face right against Kryten's, leaving a brown makeup smear on Kryten's forehead. The mark is gone in the next shot. (00:19:45)
Stasis Leak - S2-E4
Continuity mistake: When Rimmer is talking to the captain while he is dressed as a chicken, the blue bucket moves between camera cuts from being hung up on the large canister, to being on the floor next to Rimmer's bed. (00:20:35)
Quarantine - S5-E4
Visible crew/equipment: When Lister wipes down the biohazard cabinet, a boom mic can be seen in the top right of the screen. Also, just before the camera moves past the pillar, the entire microphone and arm can be glimpsed. (00:05:00)
Continuity mistake: When Rimmer walks down the corridor, his hair is a mess. When he enters the medi-bay it is tidy. (00:25:25)
Other mistake: Kryten places Rimmer's light bee on the floor, then begins the process of reinitialising him. As the process finishes and Rimmer looks at Lister (who looks away), the light bee, which should be hovering within his torso projecting his image, is still visible on the floor between his feet. (00:06:00)
Continuity mistake: When the Cat is kissing the photo of the mermaid, in the next shot the photo has disappeared. (00:24:50)
Emohawk - Polymorph II - S6-E4
Visible crew/equipment: When Starbug gets hit, as Rimmer says 'damage report' a boom mic can be seen on the right side of the screen. (00:07:25)
Rimmerworld - S6-E5
Continuity mistake: When the crew walk through the woods, the first shot shows Lister, Kryten and the Cat walking with space between them. In the next shot they are walking shoulder to shoulder. (00:20:45)
Timeslides - S3-E5
Continuity mistake: A blue fan appears on the golf course in the middle of the scene from nowhere. (00:01:30)
Emohawk - Polymorph II - S6-E4
Visible crew/equipment: When Lister says "Bony butts our move lets' just before they are fired at, a boom mic is visible to Rimmer's right. (00:06:40)
Continuity mistake: When the Cat jumps up to grab the mirrorball, a comb appears in his hand from nowhere before disappearing again. (00:20:25)
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.