(URGENT) App has stopped working

[Darren_Murphy]

See here…

Important Change: Hide User Emails is now default

Email Anonymization / Hide User Emails is now on by default for new apps, and you must choose to collect real user emails if you want them. There’s a bug where this setting may change if you open an existing app in the editor and you have never set the setting before. We are rolling out a fix to prevent this setting from changing when editing existing apps.

Note that there was a bug when this was first released, perhaps you were a victim of that?