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.
Revealing mistake: During the scene in the space station's dining room, when Craig Charles is making a speech explaining that they should escape, he stands up and pours himself a glass of Bucks Fizz. Craig fills the glass too soon (half way through the speach) and must realise, as he pours the drink back into the pitcher, and then begins filling his glass again.
Revealing mistake: In several episodes, but mostly in series 6, we see lots of profile camera shots of just Lister and The Cat at the front of the cockpit in Starbug. Quite a few times you will see Lister mouth The Cat's lines so he knows when to start speaking and what to say.