DMZ and OpenVPN question

[asiawatcher]

So i have an OpenVPN server setup for pfsense for both site to site and incoming dial-in users but i want to setup DMZ for a synology NAS that is on my lan and runs web/ftp and other servers

My question is if i setup the DMZ to forward all incoming traffic to the NAS then the OpenVPN site to site and dialin users will be forwarded to the NAS as well and not pfsense ?

How can i setup all incoming traffic to be forwarded to the NAS (all ports without having to port forward each one) EXCEPT the OpenVPN ports which i want them to go to pfsense only ?

Thanks