Seems to be missing a corner and will not load? Anyone else? The error says "Missing corner left"

Yeah I tried it out too. It does give that error in trying to load it. I am guessing its either missing dependencies or Tengtor didn't include all the associated files.

True, as I didn't wrote the mod I can't say why and also don't have the capacity to fix it. Originally the mod is created by so maybe he can fix it. https://mods.factorio.com/mod/IndestructibleWall-2

I just wanted to have indestructible walls and found the mod that I used prior to 2.0 updated this one as well. I like it more because it doesn't add a new recipe . https://mods.factorio.com/mod/MazeWall_2

Seems like it might work as intended if it is loaded with IndestructibleWall-2. If that fixes it, I suggest adding that mod as a dependency.