re: BAT files, Poser Outlaw's old script - Poser OBJ Export to Cycles (meaning, Blender) script may be helpful, one that that worked with the mcjteleblender2 exporter before Poser 11 had Cycles natively.

It has sophisticated examples of PoserPython working with folder naming, renaming and also making(!) and calling a BAT file.

from subprocess import Popen

Popen(runBat, cwd=dst)

It also seems to be getting something called basefilename to get the scene filename, a method unknown to the PoserPython Methods Manual.

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