Other mistake: Throughout the film, you can frequently see many people's faces blurred, phone numbers blurred, store-fronts blurred, etc. This is because the production could not afford the rights to show these people, places and things, and simply blurred them out.
Other mistake: The head of the animal that Guy is wearing when he first meets Eep is not positioned in a way that he would be able to see out of it when he holds his hands up to defend himself.
Other mistake: When the title card "FLYING MONKEYS" appears on screen, during the opening fly-over shot, if you look near the bottom right of the screen you can see something briefly move into, then out of, shot. (00:02:28)
Other mistake: Travers arrives in Los Angeles and is seen at the airport and the hotel a short time later with just a small suitcase and a smaller carry-on bag, yet she has far too many clothes-suits, dresses, skirts, sweaters, blouses, sleepwear, shoes, and other accessories-than could possibly fit in them. She is seen leaving L.A. with an additional suitcase, but the third one appears to be one that is just used for carrying the big Mickey Mouse stuffed toy she takes back to London.
Suggested correction: There's nothing saying that she had to have taken all those clothes with her. It's possible that she had more clothes sent on afterwards. Maybe the extra clothes belonged to the hotel/studio etc. Maybe they were rented. Who knows? Just because it's not explained, doesn't make it a mistake.
Other mistake: Originally when BJ introduces himself to Kid, he acts as if he can't recognize him. However, later on Kid gives BJ a scrapbook showing he has followed him all these years and would definitely know what he looks like.
Other mistake: Barbara and Violet are talking in the car after returning from the funeral and all of the windows are closed, even though great effort was made to convey the fact that temperatures were in excess of 100°. They spend three to four minutes talking in the car and neither even breaks a sweat, when in reality, they could not have sat in a closed car in that kind of midday heat for more than 30 seconds or so without becoming incredibly uncomfortable.