I am trying to setup DDNS on my MOFI4500 Router for my Dynu domain: zeldasloft.freeddns.org. Available router options are shown in the attached screenshot. I've attempted to set up without success so far.

I've included the dropdown menu options not shown in the screenshot:

"Event Interface" options: WAN/LAN/VPN/USB/MODULE
"Source of IP Address: options: NETWORK/INTERFACE/URL