Other mistake: Even though it is snowing throughout much of the movie, none of the snow seems to stick to any of the characters' fur. Even during the fight scene when they are rolling around in it, they are never covered with white.
Other mistake: The fire truck passing by Nani on the way to her destroyed house has the same license plate as the gas truck that Stitch hijacks.
Other mistake: When the Pirates are arrested in Nineveh, another soldier walks up to Jonah and knocks him out with a fish. When this happens, Jonah is wearing the Cheese Curl hat. When he comes to on the Slap of No Return, he is wearing his turban again. Would the soldiers change his hat?
Other mistake: In the beginning of the movie where Baby Jim is talking about Treasure Planet, he crawls under the top sheet of his bed that has been folded half way up the bottom of the bed, and peeks out the bottom. That's fine and all but then his mother straightens out the sheet and covers him up. You then see that the part he just peeked out of was the folded part so he shouldn't have been able to peek out.
Other mistake: Fleeing with Little Creek from the fort, Spirit destroys small railing to free horses tied to it. But after the pole gets torn off, it leaves an empty space on the ground, without any hole or at least broken remains.
Other mistake: Eleanor is eating a corn dog with a fork at the ice rink snack bar. Corn dogs are not listed on the menu though.