Sorry I'm a bit late.

Not exactly what you are looking for, but if you are using ProSeries on Network. You could use your Mac for shared folder purpose (Google search for 'Setting up Samba on Mac'). Or better yet, get a raspberry pi (https://en.wikipedia.org/wiki/Raspberry_Pi), and set it up as shared drive folder. The raspberry pi box is tiny and uses very little power. It would save you money for building a windows machine + license.