When Lister, Rimmer and The Cat first walk through the saloon doors, outside The Cat's large hat is on his head, but as the shot changes to inside, his hat suddenly changes to hanging behind him on his shoulders.
When Lister, Cat and Rimmer are in the science lab (just before Kryten's dream begins) Rimmer is wearing his red suit which means he is soft light. In this scene he leans on the top of the unit where Kryten is lying (but if he is soft light he shouldn't be able to touch anything). He doesn't become hard light until later in the episode.