Failed to find object 'Object None.None' only in Build

Sadly not.

I read something about that this is maybe caused by arrays and how you initialize them.

I did the worst and disabled this error because it made the log file hard to read. (shame on me!) I didn’t test this after the update to UE5, but all of my logic works as it should.

In theory, this should be solvable by initialize every array/variable/struct (structs cannot be null/empty?) before store them.