Does the help desk send and receive email okay with the configuration you've applied? If not, you'll need to open up the ports to allow the connection through.
As for accessing from other machines, you need to configure DNS settings, additionally you'll need to port forward to get through any firewall you have.
I would recommend setting up HTTPS too, which requires a certificate.
While it is possible to run on your personal instance of Tomcat by default WHD installs its own contained instance. Have you checked the firewall to ensure the correct ports out open inbound?