The Vectron primitives and operators can be created from the 'Octane Vectron' panel of the 3dsMax Geometry tab.
They should be straightforward to create and edit, with a simplified wireframe mesh visible in the 3dsMax viewport.
The primitives currently available are: Box, Capsule, Cylinder, Prism, Sphere, Torus, Tube.
vctrSample1_Primitives.max
The operators currently available are:
Clip, Ink, Inset, Intersect, Offset, Substract, Union
The Domain operator uses SDF object (like Volume SDF vdb), and is not fully functional in this version.
vctrSample2_Union.max
Note that there are no UV available; instead, a XYZ to UVW projection can be used.
vctrSample4_Materials.max
To apply different materials to instances, you can use References for each material instead of Instances.
You can then create instances of those references, that will share the same material.
vctrSample5_Instances.max
Max samples: