Even if you pushed the boundaries right to the wall, the game should not make a corridor embedded this far. As I said, it should be max 1cm. I'll be adding some automatic tests to validate room generation to make sure that all accessible areas are placed within play area.
If it is possible to send a log for when it happened, it would make it easier to fix it.
Thanks for confirming it is actual safe area being used, I was getting a little bit paranoid that it may sometimes read larger one.