In the instructions it shows it as parts that are selectable. When you import into FreeCAD it briefly shows the individual parts listed but then collapses into a single item and I can't figure out how to expand it again. Would be better to select and export individually but the single STL can be broken down and edited to work otherwise. I'll have a bit more of a play

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EDIT: It was to do with the import .STP preferences automatically combining the objects, after changing that setting and importing the parts are now selectable for individual STL export. The files may still need some work to make them printable, resin prints would be ok.
(Files are now zipped into two sets, see later posts)