Revealing mistake: When Anna and Hans are dancing in front of the lighthouse, we don't see the shadow of the railing or the ground they're standing on.
Revealing mistake: In the overhead shot of Gordon waiting for Spencer at Knapford Station, you can see that the bushes on the far left track aren't rendered properly, as they appear to overlap the rails.
Revealing mistake: When Jerry and Tom are tripping Mr. Bigley into the trashcan, neither them nor Mr. Bigley cast a shadow. But Bigley did in the previous shot, where Tom and Jerry did not. (00:52:20)
Revealing mistake: As the gang is watching The Phantom on the security monitors, he turns around and takes off down a hall. The only lights in the hallway are suspended from the ceiling in the center. Yet the Phantom's shadow is cast to his right on the wall, when there are no lights to his left. (00:10:50)
Revealing mistake: Whenever Ralph is driving Travers in the limousine and the exterior of the car is seen in a long shot, there is no one riding in it other than the driver. From every view point of the windows that can be seen, there is no passenger inside where Travers is supposed to be seated.
Revealing mistake: Close-up views of Billy riding Allie on the mini-bike (trying to escape the men following in the Jeep) did not include the lower half of the mini-bike; they were probably on a platform/trailer being pulled by a car. A 12-year-old (?) boy would have difficulty steering and maneuvering a mini-bike with a rider similar in size/weight and would have undoubtedly wrecked when he turned his body around from the waist up to look in back of him at the tailing Jeep. Billy also kept turning the throttle. (00:25:40)