As already metioned here, the right wall has inverted shading from both sides(give it an upvote).
If you look closer to these walls, you´ll find some inconsistencies. These are easy to reproduce and as a little help, i made this image. I will refer to 1,2,3 from now on.
I should also mention, that i will always look at the walls with flashlight on and from north to south, which means i didn't looked at the wall, turned around and then looked at the otherside. I looked at it, walked past one side, went back und the walked past the other side.
Top refers to the top side of the small cut out and bottom to the bottom side of the cut out.
Here are the results:
- Wall/Wall Conveyor Perpendicular/Door Left/Door Center
- Wall Conveyor 3x/2x/1x
- Door Right
So as you can see, there are som inconsistencies there, but it gets more inconsistent when you turn around and walk past the wall from south to north. Every light and shadow switch positions, every 1 will be a 2 and vise versa and every 3 will be a flipped 3.
This also works with east and west and every other direction, i just used north and south as a example.
I hope you understood everything. If not feel free to ask :)