Other mistake: Louella Parsons walks out of a screening of Citizen Kane before it ends, but later tells Hearst that Rosebud was Kane's sled. She shouldn't know that, because the identity of Rosebud is only revealed in the final scene of the movie. And if she disliked the movie enough to walk out on it, it's improbable she went to see it a second time.
Other mistake: The chain "securing" the lock on the boarded up "Metro Christian Shelter" is in some inexplicable way on both sides of a 4" board that is taut between two other parallel boards. However, when the men are using the bolt cutter, the right side of the chain extends from a hole in the middle board, and the left side goes around the side of that same board and then around a pipe that is not originally there. The board that is to the left is missing. (00:17:17)
Other mistake: When the student body presidential candidates are giving their speeches, "Monarchs" is on the Gym floor, and not "Wolverines." This is because the school where it was filmed, Papillion-LaVista, their mascot is Monarchs.
Other mistake: It's reasonable to assume that the house can hide small things like posters and even shelves when projecting images on the walls. When Ben's two friends arrive for the party, one of the walls shows an image and the couch disappears, and that's just way too big of an object to simply phase away, given what we see that the house can do.
Other mistake: In the ending credits of this movie, it says "Cast (in order of appearance)" and the first character to be mentioned is Rose, whereas, in the beginning of the movie, Dorothy is the first one on the screen, and, the first person who talks.