I am new with Dialux. This software is convenient and powerfull, I appreciate it

I am doing my first simulation. I have to create a 14m X 18m room with interior dividing walls. There are doors in these walls. My questions are :
- what is the best way to create interior dividing walls? I use extrusion volume, is there another method?
- how can I insert or simulate doors in theses walls?
- is it possible to set if the door is opened or closed?
I upload an image of the result I would like to obtain.
[attachment=0]dialux door in interior wall.jpg[/attachment]
Thank you for your help.
ericb