Hi there, I posted this question as well a few days back; i am on a mac and i was confused as well - as Preview in Leopard does not support the png transparency (shows up gray) or maybe it does, and it's just a coincidence that the gray back in preview is the same gray back as in poser! Exported png's ARE transparent, but even Bridge and Finder shows them with a white background instead of showing thru whatever color is beneath. I guess programmers of apps had to decide how to portray transparent images, and it's not consistent. But not much in life is, like the availability of electricity in this country. We are going to have 11 hours of outage per day, all on an insane rotating changing schedule...