Once 2 places the voice box into 9, the zipper remains open. However, in the next shot, 9's zipper is closed. The following shot has the zipper open again. 9 is later shown zipping his zipper closed.
When 5's map blows away, it gets caught on a piece of wood, but then blows away further when 5 and 9 approach it. However, when 5 and 9 are in the cave, 7 knows that they are in there because she sees the map caught on the piece of wood.
When 9 meets the twins, they open his zipper. During this scene, several close-ups show 9 with the zipper closed and open again without anyone closing or opening it.
When the Seamstress is sewing 1, he falls and the coin falls off his hat. However, in the full shot, 1's coin is back on his hat.
When 9 first sees the glow from 2's candle headlamp, the camera angle abruptly cuts to show him standing in front of a body dressed in a distinctive military uniform. 10 seconds earlier, a wide-angle shot of him in the same location only showed him amid rubble from a collapsed wall, with no sign of the body.
When 1 marks 2's number off on the calendar, it is under Thursday. 3 and 4 (also marked off) are on Friday and Saturday. Sunday's number on the next week cannot be seen, but then Monday is numbered 5, and the numbers continue from there, ending on 10 for Saturday. The following week follows the same pattern, skipping Sunday, then starting on Monday with 11, then 12, 13 before the calendar can no longer be read.
Before the Seamstress is attacking, there was a quick shot of 8. His mouth was sewed so he couldn't scream for help. Why didn't the Seamstress sew 1's mouth closed?