Paring guide: http://www.tp-link.com/en/faq-258.html The utility for MAC cannot run on El Capitan? http://www.tp-link.com/en/download/TL-WPA4220.html#Utility http://www.tp-link.com/en/faq-398.html

Sorry but I didn't get you. Are you talking about TL-MR3020? It is working in 3G/4G mode with a USB dongle, right?

Reset and reconfigure it. If the problem continues, replace it under warranty.

vpn pasthrough? Are you sure? We don't need to configure it normally. http://www.tp-link.com/en/faq-558.html

The one on their website should be the latest firmware. After upgrade, your problem has not been solved?

You have to able to add WPA281 in existing powerline network first. http://www.tp-link.com/en/faq-258.html If you press the button to clone Wi-Fi, you'd better place WPA281 and your router next to...