Can VRayMultiSubTex Display multiple maps in viewport - ?

[SnipeyX]

I'd like to use a VRayMultiSubTex map in a material workflow that would require displaying multiple subTextures across multiple objects (one texture per object, but from a single material). Single material with multiple texture maps assigned via face ID, just like a MultiSubObject Material would have.

In the case of a MultiSubObjectMaterial, each Sub Material can display it's own texture map. Is this not possible for the subTex map? I'm trying with Vray Next update 3.2 and Max 2021. I've tried regular Shaded and High Quality display, shaded & realistic material display, etc but it always seems to only display the texture that is in Channel 1.

Guessing it is a Max viewport limitation, but if there is any solution, either using VrayMultiSubTex or perhaps some OSL shaders - I'd be keen to know!

[hermit.crab]

Currently, the viewport preview of VRayMultiSubTex is not supported. This seems to affect the same setup through OSL shaders as well (OSL: Material ID plugged into the index of OSL: 1 of N color). We need to investigate further to see if it is possible within the host platform.

[braddewald]

I never use the MultiSubTex because with the Multi-Sub-Object material at least it can previewed in the viewport. Without that feature, it's pretty much useless since you have to render to see what it will look like.