This has been fixed in Church Center App Build 342 (v2021.3.22)
We’re aware of an issue with pre-checking from the Church Center app with Registrations Integrated Events. If there are no locations, the app will crash.
A new Church Center update will be coming soon to fix the issue, but will not make it before this weekend, March 21, 2021.
If you need a fix before this weekend, add at least one location to your Checkistrations events and you shouldn't run into any issues!