Dabblings.

Not quite sure what will happen but something might:

Sketching ideas from, errrr, 20 years ago??

 Thanks to dumptruck's tutorials , I made a box, and then another box.

  

A bit of fannying about...

 ....and I made a slightly better box. A fair amount going on here with skybox, fog, undulating and phonged rocks and ground terrain, coloured lighting, multiple lights in the pillars to get a glow and surround lighting, a proper spawn point out of a blocked off cave, etc.

 More sketching ideas....

Next plans include making some detail / structural prefabs to get a consistent theme, then see if I can block out a layout roughly similar to my original idea. And, errr, learn Trenchbroom at the same time...

OTOH, bitches....