I managed to get it working, a bit slow and not many seeders though. See below for the settings screenshot. If you're behind a firewall / router, make sure that you open a TCP / UDP port for this, and in the Incoming TCP Connections / In/Out UDP Packets, specify the port. Connect to the publictracker configuration in OpenVPN.
To be honest, I think it's a rather poor client, something like Emule or Frostwire. I suggest using uTorrent and a private tracker, such as IPTorrents instead.