If the gateway is not the default route, then every machine behind the server will need a route back.
One On one of the machines to which you are trying to connect, create a route:
route add -net 10.207.40.0 netmask 255.255.255.0 gw 192.168.0.1 up
Where 10.207.40.0 is the OpenVPN subnet allocated by your OpenVPN server and 192.168.0.1 is the LAN address of your openvpn server.