In the hangar when Jack preps the plane, he pulls the propeller in a clockwise direction. However the pitch of the blade indicates that the engine should rotate counter-clockwise in order to fly.
Characters are moving around in the ceiling over the airport lobby without any concern that the suspended panels will not support much more weight than a cat. Bruce Campbell does put his foot through one tile once.
Jack tells the remaining alien "The body count is five to five," when in reality the humans at that point have lost six.