Buffalo WZR-G144 on DD-WRT setup problems

[ascanio1]

This threat is not connected to my other threads about antenna gain and channel bandwidth.

I run an Asus AC66U router broadcasting 2 networks:
A) 2.4GHz 802.11n only
B) 5GHz 802.11n only

I am testing this Buffalo as a possible additional third network
C) 2.4GHz 802.11g only

But, so far:
> Clients cannot access internet this AP (WLAN or LAN);
> internet from WAN (Asus) works fine: tested w/ laptop;
> 30/30/30 reset on Buffalo
Setup as per images attached.










Please, can you advise me how to get it running?

 

[ascanio1]

This is one more image of the setup: