When Gob is doing his coffin trick, the camera mounted on the inside of the coffin lid disappears and reappears several times.
When Michael is comforting Lindsey in the kitchen, his watch goes from 9:30 to 9:25, then back to 9:30.
When the family goes to the attic after the funeral, the blue screen outside the window is clearly visible. It appears that an exterior animation was left out in post production.