Figures are cr2, props are pp2, figures can also be set-up as props, and turned into smart-props as well, (just a case of adding a line telling Poser the figure is a smart-prop), but even though the extension is renamed pp2, they still remain figures in reality, you can't edit them and resave them as props, they need to be saved as figures again and then turned into props once more, though setting up figures this way as props is a bit easier than making them conforming figures.

Cheers

Billy