Welcome to CabWriter. CabWriter itself doesn’t have any special tools for doors and windows. You simply use standard SketchUp tools to punch a hole in the wall wherever there’s a door or window. If you want to get fancy, you can get a huge selection of pre-drawn doors and windows on the SketchUp 3D warehouse. Me personally, I just punch holes in the walls most of the time as I am less interested in a realistic looking door and window as I am with the location of them. Once in awhile, if a customer requests it, I’ll actually put a door or window in.
It does point up that you want to become moderately proficient in SketchUp itself before tackling CabWriter which rides on top of SketchUp.
Hope this helps…