You need to get your sys admin to configure the firewall to allow packet redirection for the newtella port. For example, if you have set up newtella with port 6346 (the default), ask him to configure the firewall to redirect all packets for that port to your computer. If your company has more than
one newtella user, each should use a unique port. If you use DHCP, then he will have to write a script to capture your dynamic IP address to configure the firewall.

You should also go to the advanced setup screen in newtella, and type in the IP address
of th firewall (or whatever interface the WAN sees) as the search response address.