Unable to access Ubooquity remotely since upgrading to 3.1

I had Ubooquity successfully running under 2.1, but when I updated to 3.1, I stopped being able to access my library remotely.

Since I was upgrading to 3.1, I did a clean install, and left all firewall and router configurations the same. I have the standard port forwarded on both Windows Firewall and my Router's Firewall.

The only thing that has changed is the new version of Java with which I understand some people have had trouble. I haven't been able to find any firewall rules related to Java to change, so I'm at a loss as to why the connection keeps timing out.

I have other services (e.g. Plex) forwarded correctly, so there's something going on client-side. 

Any ideas?