I'm getting Error Connecting to Server when I first start.
I saw this recently after doing a lot of testing and mucking around with Gizmo and servers. I couldn't blame JRemote2 specifically. It didn't crash, just sat there trying to connect forever, or gave a connection error. I may have changed the Authentication Username and Password, so that could have been the cause. Could be unrelated. When it happened I didn't have JRemote 2.0.8 of course. It sounds like you found the issue anyway, reading further.
Clearing the App Data fixed the original issue for me.
One anomaly I found when I couldn't connect to any server was that JRemote2 landed on the server selection page, the one with the WOL link, and the
hamburger menu didn't work on that page. So I couldn't get to the "My Servers" page via that menu. I did (just now, after updating to JRemote 2.0.
discover that I could get to the slide-out drawer using the Android back button, which showed the "My Servers" link, but that link didn't do anything. I just went to Settings, backed out of there, and then used the back button again and the
slide-out drawer displayed with no content.
Just restarted JRemote 2.0.8 with no servers running, connection failed of course. Hamburger menu still doesn't work. Settings menu worked, so I turned off "Autoconnect to last server". That still left me unable to get to the servers page where I could edit the Username and Password to get JRemote 2.0.8 to connect.
So currently, if a user changes the Authentication (insecure) Username and Password on the server, they will need to clear the App Data in order to connect again. Or add a duplicate server record I guess, as that function is available on the server selection page. But there is no server delete function yet, so that would be annoying.