Not sure how much help it will be, but getting a nice screen grab or 5 from the scene where Hicks is showing Ripley the functions of the Pulse Rifle.
From that you can get a nice outline of the whole colony.
I used to have one I put together but........I've no idea where it is now.
You can do the same thing from the floor plan they go through right before and after they zoom in.
Also you may wish to contact this gentleman.
http://aliens.humlak.cz/aliens/aliens_papirove_modely_gb.htm
He has created from scratch 3D papercraft models of most of the colony. I know how detailed they are because I've printed and built them myself. I think he would be of great help.