"As popular as Macs are in the 3D CG world, surely there must be a similar tool for us Mac users?"

A text editor.

You've got to remember, and I'm saying this with all fondness, Poser is the CG ghetto...Thank god for Python or Mac users wouldn't even have the meager Poser utilities that do exist. In a way it's a good thing because you are then forced to dig deeper into the inner workings of Poser files rather than rely on the convenient solutions that many windows users take for granted. I think that the fact that Poser is an app with an emphasis on ease of use for hobbyist's and pre-made content also plays a role in this. Does a hobbyist need to edit a Poser file? Nope, it's a series of clicks and dial spins for a majority.