[Oddball.woof]

Just take practice using mesh vertices, like the LOD vertices.
Alot of trial and error.
Make a mesh from a brush, I usually use 5x5, then press v when mesh selected and plug away.

My maps is being delayed by a major pain in the ass Radiant, has screwed my last few versions and I have to keep restarting. The more you edit a map the more errors seem to creep in from all the saving. Weird stuff starts happening brushes move slightly, LOD verticies start spiking.
GGGGGGRRRRRRRRRR feel like I am editing the same thing over and over groundhog style. I even had to take the whole map apart and rebuilt it from them because of some weird no-existsnt doors that appeared from nowhere.
Can't say I have made much headway. I need to do some more rebuilding fixing stuff that was fine before, like textures that have suddenly gone nasty.