I only just made it as I had 5hp in one place and there were 2 scientists in the ladder room. I lured them out one door then ran round the back and through another door and made it to the stairs. Felt like an intense escape. Really good idea having some rooms with 2 doors. Also having enemies only in rooms and being able to see what's in the rooms before opening doors is really good because you can wander around think strategically as to how to tackle the level. If the walls blocked sight then the game would be far more luck based.