Forget the app and fluctuating points.

Put points on reprinted cards sent to all players free of charge, take the financial hit and learn a very valuable lesson.

Use good requirements gathering, good design, proficient coding, excellent testing and QA.

Then issue beta tests ahead of release to iron out problems.

I have developed for 30+ years in financial services. If I produced software the way FFG have I would be permanently out of an IT job.