Revealing mistake: Holly's night cap is in front of the edges of his monitor. It should fade into the white border of his screen. (00:05:25)
Revealing mistake: During filming of the this episode, Craig Charles was called away for the birth of his son, Jack, so production manager Mike Agnew stepped in. Although Lister is wearing a space suit at the time you can still tell which part is Mike thanks to a continuity error - Mike forgot to put on Lister's plaster cast. (00:15:15)

Revealing mistake: When Lister uploads his memories, the wide shot shows various videos of Rimmer in the background, but in the close up it shows a plain white screen. (00:17:55)
Revealing mistake: The square bluescreen outline can be seen in the wide shot of the obervation dome scene. (00:24:50)
Revealing mistake: When Rimmer and Lister are in the observation dome, background stars can be seen on Lister's locks and on the top of his forehead. (00:25:40)
Revealing mistake: When Lister and the Cat drop the gravestone and break their feet, you can see that it does not land anywhere near Lister's left foot. (00:26:55)






Chosen answer: In-universe, after leaving Red Dwarf after his first appearance, Kryten managed to crash Lister's space-bike into an asteroid. Lister found his remains and decided to rebuild him, however, due to the high level of damage and Lister's questionable repair skills, he was unable to recreate Kryten exactly, leading to changes in appearance, personality and accent. In reality, the original actor wasn't available, coupled with presumably practical concerns about one-off makeup as opposed to makeup for a regular cast member, so some visual changes were made.
Tailkinker ★