When you are connecting to a remote Host/Agent from Viewer that means that you already have the corresponding record added to the address book :) So there is nothing to push anymore in this scenario because you already know the ID of the remote Host.
Currently, there are three methods of getting a remote Host ID information and add it to the Viewer:
1. "Manually", which means literally noting down the ID or getting it from the remote user via email, Skype etc.
While you can go either way, the easiest option is #2 and the most complex option is #3. Option 1 (direct connection) is good if you have access to your router on the Host side. This option provides the best performance and speed possible.
I have been told the problem is my network although I have been using competing products without an issue..
I am sorry, but the fact that competing solutions work doesn't necessarily mean that Remote Utilities may not be blocked on a router or antivirus/firewall software level or otherwise. We don't know the specifics of your network, your router firmware, security settings, corporate policy, IP/website filtering policy - the list goes on and on. How are we supposed to resolve these issues while not having access to the environment itself? It's only the system administrator of that specific network who can help you figure out why a standard TCP/IP application such as Remote Utilities cannot (or isn't allowed to) send packets to a remote server (or directly to Host for that matter).
Could you please let us know what you specifically select in each configuration step. You can simply take screenshots and post them here. I'm especially interested in Step 3 and 4, and also the Host configuration step (provided you didn't select "Skip Host configuration settings" in step 4). Then we'll try reproducing the issue.