I have finally solved this, but it is a true PITA. Omitting ANY step, or changing the order, makes it fail.

I basically am using MAC address cloning, VPN, and VPN server for DNS.

  1. Associate GL-AR300M with guest wifi and save (auto reconnect).
  2. Power OFF GL-AR300M.
  3. Associate laptop wifi with guest wifi, log into captive portal, and verify internet access.
  4. Power up GL-AR300M and wait for red (wifi) LED to start flashing.
  5. Associate laptop wifi with GL-AR300M and log into admin page.
  6. Clone laptop wifi adaptor MAC address to GL-AR300M.
  7. Start VPN (I use PIA) with opvn config file for server-by-IP and TCP port access.
  8. Enter IP addresses for PIA’s DNS servers into GL-AR300M “custom DNS” table.

You now have a working internet connection through the VPN. I am logged into this board using it right now.

whew.