External FQDN for Webconsole
I think you'd better to use FQDN instead of IP address. That way, if you register that FQDN in your internal DNS and external DNS you will have access from both internal and external network.
Assuming you have your MobiControl management and deployment server running on the same MS server host hardware, you should be able to open your web console from internal or public network without any problem if you leave the "Management Service FQDN" field untouched from the default (which should be your server hostname or empty).
According to some MobiControl documentations, this field may be needed for v14.x implementation with multiple management servers.