I'm using the router as a stand alone internet facing gateway/firewall/router with WAN port1 (2.5g) as the WAN port connecting to my ISP via a Static IP while I use WAN/LAN port2 (2.5g) to provide connectivity to my wireless router for WLAN clients, and a wired router on LAN port3 (1g) for secondary clients. 

The problem I'm having is my wireless router a GL.iNet ML6000 needs to be able to see my PUBLIC ip which it cannot; I was advised by the router that I'm in a double-nat configuration, and suggest that I setup the ISP facing router ER707-M2 to allow port forwarding or use DMZ so the public IP is seen by the serices I access remotely on the wireless router, and it  will function correctly, so my questions are how do I either disable NAT on the ER707-M2 or port forward so my remote services will function correctly?

Any and all help you can provide with this matter is appreciated in advance.