Basic Driven Keys should do what you need without ever needing to touch, think about, or even know that The Editor That Shall Not Be Named exists, even though Driven Keys actually are instances of The Forbidden Toolset . Here's a simple RGB material using a Switch Texture Node driven by User Data ...

If I understand what you are asking, you can do it via Blender itself instead of through Octane. If you transfer the high poly object's UVs to the low poly mesh you should be able to bake the material on the high poly object then copy it right onto the lower poly mesh.
https://www.youtube.com/watch ...

I don't mean to sound patronizing, since I do this to myself all the time: Have you checked to make sure that your C4D render settings have Octane designated as your renderer instead of the default Standard renderer?

thanks but there's no access to nodes at all in AC (afaik)
Ouch. Sorry to have mislead you. If ArchiCad supports single sided polygons or polygons with different materials on each side, you might be able to use ssps or dual materials per poly to act sort of like one way glass, blocking light from ...

So I was wondering what the best way is to create an Universal Material with the optimal BRDF model, and if it will make any significant difference.
I think it's just a matter of different default creation settings. Universal starts by default with Lambertian BRDF, and Diffuse starts by default ...

I haven't specifically used the ArchiCad plugin, but if you have the RayType or RaySwitch Utility nodes, they should let you turn off Camera Rays while leaving Shadow Rays active. If you don't explicitly have those nodes in ArchiCad Octane, take a look at the RayType.OSL shader discussion threads ...

bepeg4d wrote:Or you can just switch the Distribution type from "Surface" to "Poisson":

I've run into this before. It seems to be an artifact of the combination of the uniformity of the scatter surface tesselation in conjunction with the number of scatter child objects on it. You can think of it like harmonic resonance. Delete one of your 89 scatter objects or add one more object, and ...

Here the matter is simple: I have an object with a procedural material on it, and I want to save that procedural material as a texture, that's all.

Oh, "save". I thought you meant you were having problems using procedurals as textures in general. Yes, the baking camera is pretty straight forward ...

You're going to have to give us a lot more than that if you want a reasonable reply.