I see it as a misrepresentation on their part as to what they actually wanted, not that they're crooks, though my old boss is a bit of a creep, but that's another story--I've been contracted to only do the modeling right now; the final renders may be done by one of the local heavy hitters and I didn't contract to give them printable renders, only proofs to show modeling progress. I feel that showing prints of these lo-res images to potential donors is like one of their (the architecture firm's) clients trying to build a project using pdfs of floor plans that were sent for discussion. They've already used the incidental images for their ultimate purpose and they're taking credit.
Shouldn't we, as artists have the right to determine how our images are used, even if they're wip or incidental to the contracted purpose? I realize that some of you don't really care how these wips are used; that's ok. The funny thing is that if I had known they were wanting to print them, I would have cooked higher-res versions (and not charged extra), printing the 640x480 ones makes me look bad and could potentially hurt future business (though no one actually knows it's me, so I guess it's a moot point) (and of course the ones in my wip topic aren't watermarked or anything else, so I'm just continuing to mess up

)
I think I'm just going to walk away from this project (after I get paid for the modeling of course).
I take full responsibility for letting this happen and not stipulating at the begining how I wanted my images to be used until I was paid and the release was signed. I just feel stupid for not expecting this.