I have a model comprised of hundreds of components that users will want to scale as needed.
Edward J. Engel

Drawn in Fusion360, exported as STP. Upon downloading, loading into a local CAD program, all is fine. Scale the whole thing all at once, and many parts fly out of position.
So, many parts were drawn "in place", some were drawn independently at Zero, imported to the model, and positioned; others were imported and copied to multiple positions.

I would hope that the positioning in STEP is absolute, but I suspect that the part creation and positioning process is causing confusion. Or is F360 just unstable in this process?

Any specific do's/don't's for component positioning for a STEP file?