I agree -- putting out products that can't be publicly rendered is just a waste of everybody's time.

(The only exception, let me say it again: if you want to put out a freebie based on someone else's copyright. People do like to do private renders of, e.g., Star Trek characters even though they can't show them for profit without getting their pants sued off. Notice, you can't sell that Star Trek themed thing even if you restrict it to non-profit renders, because then you're making money off their copyright; but putting it out as a freebie is considered safe because you're just giving Trek free advertising without taking profits out of their pocket.)

The pose set question is just like the light set question.

If X (real name: Eric Westray) goes to the trouble of crafting 20 great pin-up poses, and I know it would take me hours and hours to do as well and that my time is worth at least minimum wage per hour -- I cheerfully pay him ten bucks for the poses.

The license of sale says I can't just re-sell this package as-is to other people as my own work. If I do so, X can legally enjoin me to stop and has a claim on any money I made doing it.

X's license does NOT prohibit commercial renders of the poses because he'd be insane to write that in -- why would anyone bother to buy the product? If he did include such a provision, I would be stupid to buy.

So I've bought it. Can I just tweak a few finger positions and rename the poses and sell it as my own work? I can try, but in the real world X will raise a fuss in Renderosity and I will get kicked out. (In an imaginary world where we all could afford lawyers, X would take me to court and probably win, because once he proved that I bought the set from him, the finger-tweaking would be revealed as the cheap dodge that it is. If X couldn't prove I had access to his product, though, he'd probably lose, because yes, it's always possible for the poses to be invented independently.)

Okay, someone Y (real name: Karl Marx), living every day with the horror of anyone making a buck off anything, posts a freebie pose set and places commercial restrictions on it. Can I sell his work as my own? No. Or again, I can try, but everyone in 'rosity will point out that they can just get it free; and in the imaginary world where we can all afford court costs, Y might be able to get a court injunction against me continuing to sell. But I don't think he could get even a dime of monetary damages, because the money I made pirating him did not come out of his pocket -- he never intended to make a dime anyway.

Can I sell similar or even identical poses if I didn't get them from Y but invented them myself. Of course! (I should be careful never to download his pose set, though, so as not to create false evidence of copying against myself.)

Finally, Y's readme included a restriction on commercial renders. (Why? Because he's a f**** communist, that's why.) This is not enforceable as a practical matter and almost certainly as a legal matter. Anyone who has paid CL for Poser has a right to pose and render the figures any way he or she chooses. If Y's freebie had been an original prop that didn't come with Poser, he could restrict renders if he chose, his copyright on his own original product is good. But he doesn't own Poser's posing capacity.

I might add that the purpose of copyright and patent laws in American law is NOT to lock invention and innovation up so that it can't be used. On the contrary, the sole purpose of those laws was to encourage invention and innovation by creating a way for inventors to get some monetary benefit for their work (originally, just for twenty years or so -- the misguided way we've extended the time limits has obscured the real purpose of the laws, which were never intended to keep ideas out of use.) It's hard enough for Y to carve out any right of intellectual property over poses, and if he isn't even looking for his recompense as an inventor but trying to keep invention and innovation locked up, the law just isn't on his side.

Really, all you need to do is apply common sense and decency. You can't use someone else's original work without their permission; you can't restrict someone else from using ideas or capabilities that they didn't derive strictly from your original work.