In the scene where Catherine goes to the hospital to talk to Celeste and the little boy, there is a shot of Celeste through a window with tubes going into her nose, then a close up of her face with no tubes, then back to a shot through the window where the tubes reappear.
At the beginning of the episode, when Grissom is taking a picture of the dead, ski-masked shooter lying on the floor, the shooter's eyelids flutter from the light of the flash.
At the beginning walk through, when Brass says the guys in ski masks are John Does, the camera is focused on one of the guys in ski masks and the other is behind him. You can see the hand of the one in the background moving, though he is supposed to be dead.