In answer to the last question, Carrara 8 pro is a new install for me.   Everything's new on this machine in an fresh upgrade of several pieces of graphics software and a move up to Windows 7.     I have some Carrara plugins, but I had not even installed them yet.

But unfortunately  things have now gotten even worse.

While trying to diagnose the problem, I tried to roll back Windows 7 to previous restore point, and doing so seems to have blinded my graphics card. Apparently, going to a restore point back past a graphics card update is a no-no, because now the entire operating system boots up blank (black screen, unresponsive).  I can't get a default VGA to come up, either.
The hardware is all near-new, so I'm relatively positive it's not that.

The agony is, I can't reset back to my current registry restore point like they promised it could do, because without a functioning graphics setup, I can't see my desktop and can't issue any commands to get it to revert.

I'm going to have to take the machine in for service tomorrow and pray that they can use some tools I don't know to see what they're doing and undo this mess.

I don't know who to be angrier at, DAZ, NVIDIA, or Microsoft, but software really should not cause this kind of nightmarish collapse.