When John Payne is being shown to his hotel room, the tape on the floor as his marker for the previous shot at the front desk can be seen.
When Rick is dancing with Deborah Rick tries to avoid eye contact with Vanderline. This short sequence is mirror-inverted, no doubt due to the fact that Vanderline is in the left part of the hall and if the scene with Rick and Deb would have been printed as filmed Rick would be seen looking in the wrong direction.