After the top of the Penguin's car has beens scraped off, the whole wreck is colored orange, even the parts that should be black or gray.
When Earl's daughter steps on the Penguin's feet, he is drawn with big, bushy eyebrows. Normally, his eyebrows are either very thin, or are completely absent.
When the Penguin gets in front of the rigged Batmobile in his car, the light effect detaches from the car's headlights and floats in the air in front of it.
In the shot of the airplane taking off, there is a clearly noticeable hair on the bottom of the screen. When the animation is reused, this time with the Batmobile instead of the plane, the hair is still there.
When we cut to the garage after the scene with the Penguin and the car part salesman, there is a small hair on the bottom of the screen.