An example of HW2 background created using Space Engine skybox
Background created with secret techniques:
8-bit ABGR DXT5 (also known as 8:8:8:8 for CFHodEd) was used to ensure smooth colour transitions.
Each sky box is 96MB with 2048*2048 resolution for each face.
A custom script was used to acquire the precise XYZ locations of any light sources I wanted to add to the background in-game.
To see the background without camera clipping, you might need to set farClip = 99999999 in your camera.lua
Advanced features:
Hybrid background technology -- displays the blue sensor sphere in sensor manager.
I suppose this isn't a testmap then.