Those things about giving credit to other artists in one's own images is a new experience for me. In past Terragen times (and i never used any other app), there simply never was a need to give credit to anyone, since no objects could have been imported. Or like with Poser, giving credits for the pants your little computer puppet wears ;-)
However, a few months ago, I was looking for an object to render with TG2. I searched the web for something free of charge, and I remember the author asked for credit, in case his object would become part of someone's render project.
I didn't use the object right away. In fact, it was sleeping on my HD for a few weeks before I stumbled over it again.
The difficulty was now, that no credit information was provided with the object itself, and that I could not remember from which site I got it from.
Dear unknown creator of a amazon-like figure,
if you ever see a render with your statue, which's credit line reads: "apologies - i didn't mean to steal this on purpose", contact me please :-)
Of course, the above is just a joke. It would not be right to use the object unless I am able to give proper credit in the first place.
anyway, I bet many "creditss-infringement" that happen are caused by users downloading stuff and forgetting about the source - I believe. It migh be a good advice for people giving away objects - and maybe also .tgc's, think about that - to pack a credits note with the downloadble object.
Cheers,
frank