I'm not fami.liar with the PerfectFixes, but generally any morphs designed to correct the bending of the original V4 joints would not work as intended with the weight-mapped joints.  In the case of a morph that doesn't so much correct the bending as add a certain fleshiness or pseudo-soft body handling to it, in the belly, say, you'd perhaps have to test the morph to gauge the results.  The fingers haven't been altered in V4-WM, however, and anything designed to work with the toes should presumably still work as before. 

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Cage can be an opinionated jerk who posts without thinking.  He apologizes for this.  He's honestly not trying to be a turkeyhead.

Cage had some freebies, compatible with Poser 11 and below.  His Python scripts were saved at archive.org, along with the rest of the Morphography site, where they were hosted.