After playing around with the NAS yesterday I can no longer access the root account via SFTP.
I had it setup so that I could use FUSE to create an SSHFS connection to my home pc from work using the root account and the authorized key file but it no longer automatically logs in. It keeps asking for a password even though this option is not set in the interface. I can log in automatically from a machine connected on the internal network but not outside the network.
I tried setting a password for root login in the interface but it asks for the old password and keeps telling me it is wrong. I shouldn't need to enter an old password anyway in case I have forgotten it.
I logged into the NAS and did "passwd root" and set a password but the sftp login still won't allow.
Finally, I created an FTP user and I can login with a username/password but I cannot automate the login now because I can't provide an authorized key.
One criticism I have with the interface is that I cannot find any configuration files to try and take care of problems myself. I presume all the settings are loaded in a database somewhere?