Erm.... Bad things happen when using older Poser models! I decided to use the older Roman model that comes on the disks with Poser 5 and it was more pain than it was worth. It's a beautiful model but I think P5 hates it. I believe its caused by the smooth polygons feature somewhere...anyone remember which you have to turn off to get it to stop doing this? I managed to get everything but one or two of the columns to stop "bloating", although this was the funnier example as a pic...lol..I never thought the floor might rise up to attack poor Vicky! But I guess in this pose she was ready for it! I tried taking off smooth polygons in Firefly as well as turning it off on some of the items itself in the properties menu, but I believe it may have to do with doing one of those or both or also perhaps the remove backfacing polygons as well? It only happens in Firefly mode....P4 mode renders fine....

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Yes, that would be the smooth-polygons feature causing this problem. You can turn it off entirely from your Render Options panel; otherwise, you'll have to disable it on an item-by-item basis. I think the original release of P5 had problems with disabling the feature. It was fixed in one of the later service releases.

The floor might need smooth polygons turned off and, of course, you should check that ALL the columns have smooth polygons off.