What you're seeing is a problem I've had with Modo and texture painting, for years.  Modo has a built-in feature which extends the pixel-colors at the UV seam edges by an unspecified increment, which has always solved it for me.  As reported above, I had the same issue and solution for uv2uv.  I assume it's some sort of float precision issue, with the various UV methods being more precise than Poser prefers about finding the edges of the UV islands, but I can only guess.

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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.