Corrected entry: The wall that Sean emerges from after Rennie was injected with drugs is obviously a set, because you can see the wooden props holding the wall up behind him through the doorway.
Corrected entry: After Rennie is thrown overboard, she goes to the bathroom to wash up. As she is washing her hands, a vision of Jason comes out of the mirror. If you look closely, the water in the sink has turned itself off.
Corrected entry: Jason boards Jim's boat, and when Jason grabs the handrail Jason's pinkie finger and thumb are sticking out of the glove. Jason, even though a rotting corpse, he still has these two fingers nice and healthy looking.
Corrected entry: It's obvious Jason means to kill everyone on the ship, except for the few who get off and make it to New York, but when did an entire high school graduation class consist of no more than 15 people?