Revealing mistake: When Ada and Baines leave the island the Maoris pull the heavy canoe with the piano on top across the beach into the water. From the tracks in the sand you can tell that it runs on wheels. (01:44:35)
Revealing mistake: When Ada is playing in her sleep, you can tell in the first shot of her hands playing that it is not Holly Hunter's hands. The hands are larger and masculine, obviously a male's hands.