Now i'm running into the problem Dustie said earlier. I thought you could connect 2 smaller rooms with a bigger one, like this:
But it causes transparency problems.
That makes me worried about the amount of rooms i will need to use, because everything is connected with everything, and dividing that tall room into 2 means also dividing all the rooms on the same plane into 2... Well, i suppose i will need to shorten the level if i get too many rooms.