Hi Simon,
Thanks for the use case examples. I’ve logged them along with the existing feature request.
In the meantime, There are a few other approaches to achieve the behavior that may be worth exploring.
You could put the objects you don’t want receiving shadows into a different lighting channel (this can be set on a mesh instance from the details panel under Lighting). You may then need to adjust the emissive value on the mesh’s material to make it look right.
Alternatively, you could create a sublevel for the un-shadowed objects, and hide that sublevel when building lighting.
Please let me know if there is anything else I can answer.
Best,
Josh @ Epic