I just bought Poser Pro 2010 (sidegrade from P8), and it worked great the first day.  Now, though, a mysterious problem has cropped up.  I'd been told a while ago that AO is unnecessary whenever IDL is activated, because AO is included in the IDL.  My own experience with P8 contradicted this (leaving the "Evaluate in IDL" box unchecked caused no loss of AO, but deleting the AO node did seem to result in AO-less renders), so I continued to use material-based AO along with IDL.  I decided to test the IDL-AO connection in Poser Pro 2010 shortly after installation, and it seemed to hold true this time.  My characters have two complete MAT sets.  One has both procedural gamma correction and material-based AO, while the other has neither.  I applied a MAT pose from the latter set and activated automatic GC.  The resulting render still had AO!  I thought, "Great!"

Well, sometime today, something changed, and I have no idea what it is!  Now, activating automatic GC in render settings seems to give me distinctly flat-looking renders that I recognize from prior experience as lacking ambient occlusion.  I tried tinkering with the render settings a bit.  I also tried rendering default V4 to see if my MAT poses were somehow the culprit.  I tried restarting Poser Pro and even restarting my computer.  No luck.  I would be eternally grateful to anyone who can give me some idea of what the heck's going on! 

Thanks in advance!