Really has no sense to use billboards with Octane, because this engine is mainly designed to use 3D Objects. Also, some feature as fake shadows
, are not supported. Anyway, if you need them please tell me. Well prepary a library of 2D materials for Octane. Only it's necessary to remove "Forest Material" and convert the base material, which a Standard type.
On the other side, i've done some tests converting materials from the free models, and i can reproduce the problem of your previous post (i though it was crashing in the conversion process, not after it). There is a workaround:
1) Turn off Geometry->Consolidate Materials.
2) Convert materials.
3) Turn on Consolidate Materials.
This problem is already fixed for the next beta update.