ok, that makes a good reason to upgrade to the full version
I hope support for the "d" value can be implemented soon!

Thanks for your replies!!
I have specular materials working now, but still have problems with opacity.

Specular materials: I see there is a difference when I specify Ni or not:
if I specify Ni, I get a specular material with Reflection (Ks) and Transmission (Kd) components.
if I do not specify Ni ...

I am making an open source exporter (.net/WPF) that creates obj files for import in Octane.
Diffuse materials and geometry works great, but I don't get Octane to import the specular components and opacity of my simple materials.
Here is an example I would expect to show two diffuse/specular ...