I've searched high and low and I can't find a solution that works.
I want each of my streamed levels to have their own lighting, but when I put them all into one persistent level, the editor wants to bake them all together. Hiding layers and baking them one at a time doesn't work as the editor says it can not build with levels hidden.
I then tried opening the sublevel files separately, and giving them all their own lighting as a lighting scenario level. This didn't work because only the persistent level loads in to the main level, not any sublevels, including lighting.
What am I missing?