Hello there. Sorry to hear about your unfortunate inability to play.
In a case like this - I always recommend closing ALL iPad apps and restarting the device.
Closing all Apps:
- go to your iPad home screen
- double click your Home button to bring up the background apps bar
- hold finger on an app in the app bar until X appears
- press X on all the apps to close all apps
- hold home Button and Power button together for 5 seconds
Once your iPad has reloaded, don't open any apps. Go straight to MM. See if it opens. If so - great!
If not - do a full iCloud or iTunes backup of your iPad, just in case you end up doing a software restore on it. I would recommend against removing the MM apps unless GI support tells you to. I've seen people remove the App, reinstall, only to lose their character with no way of getting it back.
Let us know how it goes.