The werewolf's tattered shirt is a completely different color than the shirt Saul is wearing before he turns. This happens throughout the movie.
Within the first 5 minutes you see a detached hand on the ground holding a gun. A left hand. A minute later you see the body it came from, but his left hand is still attached.
Sylvia's uncle, a University professor, lives alone in a large Medieval castle, which is never explained. Additionally, all of the interior scenes were clearly shot in a house.