Other mistake: When Cody stole Barney and was running from Abigail and Marcella he hid in the closet, but the girls thought he went to the attic. When he came out of the closet the door made a creaking noise. If the noise was made when he went in, then the girls would have known he was in the closet rather than thinking he went to the attic.
Visible crew/equipment: Several times during the "we're going to find a way" musical number the ankle part of the barney costume lifts up showing that the feet are separate from the rest of the costume and showing the ankle of the man inside the Barney costume it is most noticeable when Barney takes Marcella's hand and she steps on the platform.
Revealing mistake: When Baby Bop runs into the frame in the barn to ask if anyone has seen her blankie, part of her hair falls off.
Visible crew/equipment: When singing Old MacDonald the sheep handler can be seen trying to herd the sheep in the lower right hand corner of the scene.