The best way to answer #1 and #4 is to...uh...practice from home at 8am ET. Just don't click past the screen where you select the members of your group in case today's issue repeats
You'll get familiar with the screens and who the app recognizes is associated with your account and when you select them in the process.
@DCBaker answered the rest, but I'll just add that you should definitely have both you and your wife try. First one in can claim for everyone. The 2nd one in will just be told they're already in a boarding group.