Other mistake: On the title screen, there are several mistakes. First, every splash screen has the stomping hammer facing backward. Second, while the obstacles and support change based on the country/region the level the player last selected is set in, the flooring and the background are always that of a USA level. In addition, after playing a Las Vegas or London level, the sides are that of a USA level as well.
Bug: If the player returns to an area with flying boulders, they can go under them without being crushed, allowing them to clip through them.