You simply have to Control-Click the application, choose ‘show package contents’ and navigate to ‘Ressources’ → ‘Scripts’ and you will have full access to the source.
on first approach it seemed you solved the problem. But after I built the app as you instructed it did not recognize push button clicks anymore and did not work.
Viewing the script showed that it was stricly empty.
Something could be wrong with your project, it sounds like your AppleScript is not getting compiled. Since I can’t get debugging to work, I only ever build my projects in deployment mode and as a result I can’t read the source in the executable.
Do you have more than 1 target, and if so did you select the other target at the same time as changing the build style by accident. Try running the deployment version from inside project builder.