Save the route script to /usr/local/lib/openvpn/route on the client. Make it executable with chmod +x.
Remove the push redirect-gateway option from the OpenVPN server config.
Add these options to the OpenVPN client config:
setenv OPENVPN_ROUTE_TABLE 94
route-noexec
route-up /usr/local/lib/openvpn/route
route 0.0.0.0 128.0.0.0