Ignoring the use of AI, there are many things I don't understand. For example, if the song ends, you have to start from scratch, but if you select "restart," the level restarts, and with it, the song (which doesn't make sense since you can't select a level). Also, Santa's AI bothers me because in the later levels, he becomes ridiculously fast, making it impossible to beat. This is something that should be improved.
P.S.: Where's the bell?