Other mistake: At the end of the show when the misfit toys are being delivered, the elf in Santa's sleigh gives an umbrella to each of the misfits so they can glide down with the exception of the bird, who jumps off, apparently forgetting that he is a misfit toy and can't fly; as he stated earlier in the show, he can only swim.
Other mistake: In the ceiling tea party, Mary Poppins offers Bert some sugar, and when he responds that he would not like any, his Cockney accent is gone.
Other mistake: Mrs Kenton and Sylvia can't get into the study where Mr. Kenton is; there is no reason why the door would be locked. A mule can't lock it with a key and there is no debris or furniture to block the door. Harold opens it just fine from the inside without operating any particular kind of lock.
Other mistake: There were no gorgons named Megara. The three that existed were Medusa, Euryale, and Stheno.