Summary
One of our users wanted to use his FreedomBox as a 2 TB NAS. He installed Samba on it and made it happen.
He was generous enough to document his work here:
http://jgbarah.github.io/Notes/freedombox.html#installing-a-samba-server
If we ever want to implement this feature in FreedomBox, we could use his documentation for the shell scripting. Just sharing this here in case our team ever wants to implement this feature.