Again? ALWAYS make a space, that is enterable from 2 sides. Or it has to be a small room. Think of this, and use it in any way you see fit *1 door, 1 vent*;*2 doors*, hole in wall, door ect. For variation, make things like a door, a ventilation shaft, sewer, but also a walkable roof, bridge, or something like that. Make your map unique. Make something that has never been done in ZS before. You will get kudos for that. Like a bridge, that will fall down when lots of weight *say, people walk on it*. So you will have to make plans on how many will cross. Make it like so, that it's long. And maybe work with different colours of light. Not white lights, but more realistic light, like a bit yellowish.