Asus RT-AC68R OpenVPN: cannot resolve client-side IP addresses

[MightyMrMatt]

I have setup the OpenVPN for this router and when I connect from the client (Windows Server 2012 r2), I can resolve IP addresses on the router's LAN, but I can't resolve IP addresses from the client's LAN, including the client computer itself. I have added the client-side IP range and subnet mask to the Allowed Clients section, but every ping and tracert dies at the router, even though I see the route in the IP routes list. The firewall is off on the client and the client-side router has port-forwarding for the TCP port 1194.

Any idea what I am missing? I've found a lot of suggestions (firmware update, factory reset, putty to change files, etc.) but nothing seems to work.