You really don't WANT that option off -- It means you're not going to use Hijack for anything, which means you fall back to old Empeg protocol (specifically uploading and downloding are done entirely with FTP when you have hijack enabled). But follow Mark's instructions now and maybe it will reveal itself ...

Oh wait.

Is it possible you have a software firewall that is blocking passive ftp connections back to your machine from the Empeg?