I looked it up.  Had no idea what this application is.  It said, "Pegasus is a Subdivision Polygon Modeler built from the ground up for creating content for Poser."  It didn't mention anything of it's features though.  Just a few screenshots showing a short dress on some character model.

I couldn't find any forums or tutorials or anything else about it.  Hope you found a solution.  There doesn't seem to be any support or community out there for this modeler.  Did it come with documentation? You might wanna try out Blender if this doesn't work out for you.  The UV tools in Blender are incredible, and the modeling is one of the most powerful in the world.  It has every tool and capability of the biggest professional software out there, like Maya or 3dsmax, and even more!  Best part of all, it won't cost you anything but the time it takes to learn it.  Good luck!