Let's assume it's something I'm doing wrong then. Still, it'd be useful to me and probably to others to work out what is wrong with my workflow.

To provide a more usable test scene I have deleted all the objects from my original scene. The lights and cameras have been left just as they were. I have replaced the original objects with three Poser primitives for illustrative purposes. I understand it's ok to include them in publicly distributed scenes.

A zip file containing the scene will be attached in a follow up post(remove the .txt extension).

The Poser (top) and Lux (bottom) renders are shown above.

Free stuff @ https://poser.cobrablade.net/