[-=[XTC]=-Body Bagger]

Static models can be made detail using the way i described.
If you have walk trhough models just mke a box around the parts you want blocked and and add the approprete clip texture. E.G wooden chair u would use the wood clip.
As to making doors and windows detail, i have done before and apart from reducing the vis data size it doesn't seem to make much difference. When the map is being used whats inside the rooms is drawn by the engine as windows and doors don't block the view.
I have seen a tut somewhere about using hint brushes used for cutting down fps, but i didn't really understand it to well and never tried it.
Anyhow hope this helps
Craig