I have just amended the first post of this thread to include a link to show how to use Area Lighting Base on an inverted Sphere as an Environment light http://vidaru.com/creating-simple-image-based-lighting-in-daz-studio-4/77154604
Makes for a nice soft overalll ambient light with occlusion but yeah a bit slower at render times compared with other sorts of lighting but it is a trade off with what results you want. Personally I would use this method more in the future.
I know this works in DS188.8.131.52 but it seems that with the latest versions this won’t work as 3Delight will now render the normals outward no matter how an item is scaled, even negative scaling. This so called fix will hamper making the light Sphere. It seems that the normals have to be reversed in say Hexagon or Blender etc etc first. No one knows how or if the normals can be reversed in Daz Studio itself though there has been a suggestion that the Shader Mixer might be able to help.
But without access to Daz Studio I can test anything