@Elyot
Why would you reset the appliance? You should be able to configure it for your needs based on what you actually have.
The linked thread shows you, how to route upstream traffic to a certain gateway. This seems to be, what you need here.
When you set up a VPN, you can decide if you want to use it as default gateway or not. Most VPN providers pushes the default gateway to the client. That means, any upstream traffic is routed over the VPN.
The mentioned policy routing in the other thread gives you an option to direct traffic to another gateway than the default one. If your default gateway is the VPN you can direct certain or all incoming traffic on an interface to the WAN gateway. If your default gateway is the WAN you can direct traffic to the VPN with it.
If you don't want the VPN to be your default gateway go to the OpenVPN client settings and add a check at "Don't pull routes".