I still need to talk to him.
It looks I can get a watermark version, but I'll need to talk to him about how fstorm goes about translating the 3ds Max scene. For the most part, whether we're compatible with a renderer has more to do with their systems than ours.
That I know of only Arnold/MaxtoA, maybe VRay can be actually interfaced with to take any control over the translation.
Corona and Redshift I think may also have a way to tie in, but interfacing with them isn't publicly available.
So depending, most of getting that stuff to work can be more diplomacy than engineering.