Trying to use FreeNAS as the server, there are settings / checkboxes that claim SFTP works on this OS but I am really starting to not believe it. The docs say (if memory serves me) that I just need to enable SSH and FTP and they almost automagically just work with each other. Well I've tried that, and that's crap.

Under Services > FTP:
Local Users Only is checked
Default Root (chroot() ) is enabled to keep clients from wandering
TLS/SSL is unchecked

Under Services > SSH:
Permit Root Login is disabled
Password Auth is enabled
TCP Forwarding is checked (states that this enables SSH tunneling)
Compression is disabled
I have generated a private key and it's in place in the gui here.

The object is to be able to receive sensitive files via SFTP over the internet, the domain is leased / owned whatever you want to call it so ftp.mydomain.com will be forwarded to a static IP, then that static IP will have port forwarding to the physical server.
Right now the SFTP client WinSCP was erroring out with an error about no SFTP service running or this is not an SFTP server... something to that effect.

I've generated a private key with openssl which seems to work for the server, but when you try to use it with WinSCP - the client wants a .ppk version not a PEM file.

I can't seem to find a good tutorial anywhere from beginning to end. Right now I'm just trying to test functionality on a class C 24 bit network. Can anyone provide some helpful advice or maybe recommend a better solution? I like FreeNAS because if I were to present this solution to a company, the web GUI interface would make it very easy for them to add / remove users as they get more clients.