AP Mode Internet Connection and LED Query

Hello to you,

So for the last few days I have tried connecting the R7800 to the internet in Router Mode, but the router will not connect.

I use an ADSL modem, which the R7800 plugs into via the rear yellow port (of the R7800) and a LAN port on the modem. 

I have confirmed with the ISP that my settings are correct and they have confirmed that I am connected, however under the Advanced home page of the Netgear it shows a red border around LAN port and informs me that I am not connected. This is further confirmed insofar as I cannot interact with the internet.

I have tried using the default MAC address, This Computer MAC address and the MAC address of the ADSL modem, but still the situation does not change.

I have followed the advise of the troubleshooting guide p.166 under "You cannot Access the Internet" and followed the "Sequence to Restart Your Network" on p.163.

There are also online Netgear support documents which have not helped in the solving of this mystery. I am not blaming Netgear, they simply have not helped.

I have reset the device (depressing the recessed button on the back of the unit as instructed by those same documents) and used the erase option in the Advanced> Administration> Backup Settings: Erase, then entered the relevant data in to each field as necessary and also used the Save a copy of current settings option to input the data.

However, when I switch to AP mode I can connect fine.

Could someone confirm if the Internet LED on the R7800 (AP mode) should be flashing white or should it be a steady illumination (solid white) when connected to the internet? 

I can see nothing in the User Guide p.10 Table 1 "LED and Button Descriptions"

While under "Standard LED Behaviour when the Router is Powered On" p.163 it simply refers to the Internet LED as being lit.

Cheers