Duplicati Issue - probably permissions

I have managed to installed a FreeNas jail running Duplicati and after some buggering around managed to log in. I then created 3 folders in /mnt called (Install, Music, Data) and then use FreeNas to assign mountpoints to the appropriate datapools in FreeNas - so far so good.

If I then open a shell into the Duplicati Jail, I can see the mount points I have configured and cd into them to find all the files in the datapool(s). whoami says I am root

I then open duplicati up and set up a backup...

Duplicati Issue - probably permissions