Thanks, Two_dogs. I'd forgotten about the Pi and Kodi and that this combination will allow functioning as a UPnP "NAS" that can be accessed remotely for file copy and streaming.
Over the weekend I've managed to fix my current device by returning it to factory defaults and then reconfiguring so I'll continue with it for now and then go down the Pi & Kodi route either (a) when the current box fails again or (b) when Pi has USB 3, whichever is the sooner.
Thanks again.
TLXV