Other mistake: When Hoffy goes to blow out the single candle used to light the room, there's an extra second of light before it gets dark. Also, there's too much light to be explained by one candle, and no electric lights (The Germans would have cut the lights off from outside).
Other mistake: When Shapiro goes to get the teabag out for Dunbar's tea, you can see that there is a wet spot where it was in his pocket, suggesting multiple takes.
Suggested correction: Or he'd simply used the teabag before using it in Dunbar's tea.
Other mistake: When the Geneva man is inspecting the barracks, he is told that "each barrack holds seventy-five men." At best count, there's only thirty to thirty-five at any time, and the correct number of bunks.
Other mistake: 2 prisoners from barrack 2 bring in a phonograph for the exchange of Sgt Sefton's brew distillery, but where is the music coming from, given the phonograph is fake?
Suggested correction: The phonograph isn't fake. Why would they exchange a fake phonograph for a working distillery?