Just noticed nobody replied to my thread, and your neither. So I'll reply for you
I've decided to drop BSP alltogether...It's to much work to get them implemented, theyre not really working all that well etc
When this VIS portal comes into play after U6, then .x files will be my choice. Dont know about the lightmaps, but I think they are possible, as the Obsidian game thats being developed by GCEclipse uses CShop .x models divided into segments, and the screenshots showed some really atmospheric levels with lightmaps and the like. So yeah, I guess its possible.
The portal will allow very detailed .x models and with Kensupen's BSP style collision code they should be easy to set up collisions.
Im not much of a BSP expert so dont really take my word for it though
ZEDWARE website coming soon... //END TRANSMISSION//