Got forced back to the start screen after too many Error 0's, and now I'm stuck on a 2.PARAM.2 login error that won't let me into the game. Tried everything I can think of to fix it but no luck. :/ I've seen folks on twitter with the same error code too, so now I know it's not just me.
I was having login trouble last night for around an hour. Never got past "Authorizing" and it kept looping to my Google authentication login. I left the app alone for awhile and later it was working fine.
The only other thing I can think of is if you don't have your apps set to automatically update in the store like I do, you'd need to manually go in and update it. Otherwise I'd talk to a Dev
Tried both of those things, but no luck. I *think* it's a problem with the way they changed how the login works in 4.4 for currently not-logged-in users and the fact that too many Error 0's automatically logs you out via ending your session. I think maybe the forced-logout messes things up in a way the new system doesn't recognize. Made a bug report thread with details last night.