i have now edited the back wall so that it is flat, and removed one of teh windows to add the front doors, these are seperate objects and i have changed the pivote point so that when i rotate them, it apear the open on hinges, i will have these open on the animation.

i have also added the railings on the roof.

for some reason, the file couldn't find the material of the walls and has changed to the default grey, but at this stage i have actually added materials of the outer walls, whihc i got from a photo we took.