Hanged man in the third story sometimes changes his position throughout the scene.
Throughout the movie people get wet, but dry to quickly in between shots.
A killer in the second story chokes his victims too easily and quickly. It would take a lot more effort and time in real life.
When killer in the second story goes to stab his third victim, he stops just before the blade connects, revealing that the actor didn't want to hurt the actress.
Hanged man in the third story obviously isn't hanged by the neck.