Yep, untextured is another option, especially if the textures add considerable value. Again, depends on the product.  For something like a car, it's may be too easy to for people to use something like those shaders etc. thus make the textures less valuable - unique human figures would be different.

I l;ike the model EvilInnocence uses with CrossDresser, i.e. free modules for some less used figures. I was thrilled they had a free module for Pu Doll. Even if I didn't want the full product, I'd still give them plenty of good word of mouth. You don't have that many options with content, at least not Poser content. I know that some Vue content is 'node locked' to your serial number. AFAIK, the only functionality limitation is that you can't export it. Presumably with a binary format and some clever coding, you could do things like distribute a full figure and have certain features require a purchased lic. code to work. Of course, that would require support built into the application. You could say that RTEncoding is a (very) approximate implemnetation, in that it requires you to have something (a valid .obj file) in order for the product to work, but its all or nothing. With a more sophisticated scheme, you could, in theory, do a lot more, even 'rental' assets that expire after a certain period. That's probably more suited to productioon environments than Poser where someone might want to e.g. rent one of Zygote's expensive human models for a single project. 

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