Ok this helped a lot, I couldn't find a fix.
Simply, I already port forwarded the FTP port to my server. (The default is 14147, I'll use this as example)
Go to Edit > General settings, Listening port should be the one your using, in this case 14147.
Then go to Passive Mode Settings, I checked "Use Custom Port", and entered in the Range 50000 - 50100.
Then on your router, port forward 50000 - 50100 to the server IP locally.
IPv4 specific settings I left at default, reconnected my client, and bam now the file listing appears.
Ensure your servers firewall has an inbound rule set to accept 14147, and 50000-50100.
Basically what Evan stated. I can't attest to the security of opening these ports, but this is what finally got my Filezilla client and server to communicate and view files. Hope this helps someone.