Are you using two switches to control one same light? If the light just flicker, it could be caused by wrong wiring.

if you disable the Norton, will it work again?

so wired. i think you should contact tp-link email support so they can analyze this log.

there is no DHCP server in the TL-WPA9610. you just need to pair it with another plug.

i don't think so. AV2000 is the phy speed. so in the autual internet browsing, it is only 30-40% of that speed. what's more, there could be powerline interference which may lower down the PHY speed

It seemed you failed down in configuring your device. Which step can't you pass through? If the final step(connect device to your home wifi), you can have a check on your wireless settings. First...