Great suggestion.
Got it installed in a flash.
Unfortunately, it does not seem to be able to move a folder from Unassigned Devices :-( And that is what I am trying to do.
Currently trying to move my old Windows (NTFS) data onto the array. I figured it would be quicker that doing a move from a Windows VM.
Google Midnight Commander (mc). It is built-in to unRAID and it gives you a sort of text-based, two-panel, file explorer that is easy to figure out and use. Just navigate to /mnt and look around, you will be able to see your disks, including the unassigned device. Then you can copy/move from one panel to the other with some function keys.