(at around 1h 3 mins) Near the end of the movie when the Nazi truck convoy is seen driving slowly through the countryside, white lines are plainly seen painted along the edges of the road. Marking roads in this way is a safety practice that wasn't put into place until the 1970's in Croatia (where the movie was filmed), though the film is obviously set during World War II.
(at around 1h 9 mins) In a film set in the 1940s, Rayne says "Motherfucker" two times, even though the word was not common until the 1950's or the 1960's.
(at around 34 mins) The doctor says "Times they are a-changing", a couple decades before Bob Dylan introduced it to the lexicon.
(at around 7 mins) When Rayne enters the boxcar during the opening fight, she is carrying her two swords. When she is attacked inside the car, her swords vanish from her hands.