To get the stuff started, I run one OpenVPN a.t.m. but in the end I will run 2. One for use as domain users and one for our customers.
443 = WebGUI and VPN
1194 = VPN
943 = Admin page
Multi-daemon mode, so TCP and UDP is possible.
I tried to reverse proxy with one rule (Reverse proxy matching on port)
but there was suggested to split it up to each port.