Updated my volume actors to work with the new system. Also had to make it so that updating the Main Map or either of the Shadow Maps reflected on all 3.
I am also moving from a Tile Volume system that had a Child Volume for each tile type to a single Parent Volume that simply handles interaction by vector index and then use that information to update all the relevant arrays that actually hold the tile relevant data.
Using a glass material for Volume testing purposes. As you can see changing one tile affects the Shadow Maps as well:
Regenerating 3 maps is just as seamless as regenerating 1, so that is encouraging. 