You ever be building a big space station in Space Engineers and go to make pressurized environments and spend hours trying to figure out why one area will pressurize but the mirrored side wont pressurized? You've already gone up and down the corridors and looked at every wall and eventually reload the game, assuming it's just bugged, but the issue persists? It was two corners on two blocks hidden in the ceiling. Yup. Welcome to Space Engineers!