Typically this is a server side setting. If I follow, you have a home network run by a router that has an OpenVPN server, and with your Opal connected to some external location you want the Opal as a client to connect to that VPN server, and from that connect to server side local machines. If your configuration is different you might straighten me out.
If so, the OpenVPN server needs to be configured to push a route to the LAN to clients when they connect. The server configuration would contain this line:
push "route 10.xx.xx.0 255.255.255.0 vpn_gateway 500"
with those xx’s being the second and third numbers in your network.
Also, while you can connect to the VPN Server and access the internet, that doesn’t necessarily mean that you are accessing the internet over the tunnel. You’d need to do a tracert to tell. The server controls that by pushing a change in the default gateway.
Me, no connection with GL-inet either.