The solids in my world aren't being rendered when the BSP file is loaded. The compile tool does not complain until it starts the VIS tool and then it is obviously trying to calculate VIS effects on a very leaky map (floors and walls are missing from the BSP)
My main problem is resolving why the solids are not appearing in my world.
Thanks a lot for the advice - I've put some more effort into the map since I created this post. I've been running with just the CSG and BSP tools for the most part but I did do a full compile overnight just to make sure everything was in order.
I'll check out Andy's tutorial now, thanks for the tip.
And, RabidMonkey - I think I just ran BSP on normal, I'm not familiar with EntsOnly, what is it?
Thanks again