I was using the VMG1312 as a modem +router and ended up with dos protection enable and icmp blocked on the gui. I then used telnet to send the npr's command iptables -I INPUT 1 -s 80.249.99.0/24 -p icmp --icmp-type echo-request -j ACCEPT to enable the BQM. That worked well for me.
If your in bridge mode the needed settings will be in the Linksys EA8500 and not in the VMG1312. I can't help re a Linksys EA8500.
On the VMG1312 under power management you should be able to turn the LED's off but i have not tried it.