Here's a myth that goes the opposite way, and I must confess
that I helped to spread it in the past!

"Python scripts can reside anywhere on the disk."

For really simple scripts, this is true enough.  But any script that
refers to various modules, or that stores and loads data files,
needs to be in the primary or 'base' runtime of the Poser version
you're using.

Since most folks don't know or care whether the script is 'simple'
in this sense, it's always best to keep a copy of each script in
the runtime/python/poserScripts folder of the version you're using.

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