I hate to have to ask a newbie-sounding question after being here for so many years (and have the answer be something simple that I should have known or remembered), but what setting am I missing that causes Poser Pro 2012 to render my backgrounds transparent?  I have tried "Render Over Background Picture" and "Render Over Background Shader" (with an image map in the node) and exporting in .png, .jpg and .tif formats, and my background, which I can see correctly rendered within the Poser program environment, never shows up in the exported image (they become a transparent layer).

(I last worked in Poser several years ago - version 5 - and just recently got back into it with Poser Pro 2012.)

Intel Core I7 3090K 4.5 GhZ (overclocked) 12-meg cache CPU, 32 Gig DDR3 memory, GeoForce GTX680 2gig 256 Bit PCI Express 3.0 graphic card, 3 Western Difgital 7200 rpm 1 Tb SATA Hard Drives