Hey agentfarrell,
I experienced the same thing and I couldn't get the sensors or rules to show up appropriately in the browser no matter what I did, refreshing or otherwise. What ended up happening is that I flashed the firmware again and noticed that I could now see tabs, and my sensor showed up.
As soon as I changed my password, however, the interface became garbled again. I reset it back to the password that was initially provided by the router and it snapped back together, displaying the tabs and allowing me to add rules successfully. If you've changed the password, try changing it back and seeing if that solves your issue.
I can't tell if it was my password length or another property about my password. I'm using Dashlane, so I ended up setting a 28 character password with symbols. Whatever the case, I'm leaving it as the default password for now. Hopefully that helps you out.