Really funny to hear you say you found it non-euclidean because I actively tried to make that not the case for once >.< I mapped out the entire game with screenshots as I was working on it and made sure that everything perfectly lined up, so all of the distances should be more or less exact. Kind of curious which rooms felt non-euclidean to you?
I... did not think about that gap in that room at all. I kind of just assumed it wouldn't be possible to get up there and didn't check whether it was possible with enough flight upgrades.
Also really funny that you found that one breakable wall, I really did not expect anyone to find that. I had some really overambitious plans for what was going to be behind it so when I cut those I decided to just brick the wall over rather than remove it completely so that it would still be there if I came back to the idea. So, there is no other side to it right now, unfortunately.