Note, I misunderstood the first question, thought it was about light through glass-like materials lighting other objects.
The particular case you linked to isn’t yet implemented, but if Brian says he can do it in Blender Cycles then it is a matter of writing the proper shader graph and it’d be in RhinoCycles.
edit: tried quickly in Blender Cycles. It is just a matter of mixing a translucent BSDF, which results in:
I still need to wrap that particular node, but that’s a matter of 5 minutes. Eventually I can see there’ll be a material with the translucency node, a (DEV) version I could add also in short time, but such materials (currently all Cycles custom materials in Rhino) are for development, and shouldn’t be relied since they’re for test usage mostly.
edit: wrapped and a test material added, I’ll update soon with some visuals.