1. I never actually expected anyone to hit the birds with bullets so I never added the code for it.
2. It's usually because of the fade in transition on Clickteam Fusion stopping everything until it finishes the fade in, so you might have to wait 2 seconds before pressing it. I never planned to add custom fade in transitions because I was running out of time.
3. I had to think about this for hours until I decided to use one bullet per press, cuz you might kill the birds that were flying (which i never added)
4. Its meant to be an endless shooter, that's why I added a score system, 10 points per hit and 100 points per boss killed.
I will add some features like hurting the birds with bullets, having Hold to Fire as an optional or default setting, and fixing the transitions, after the jam is finished. Thank you for giving notes, since it will be useful on improving the game somehow, and thank you for playing my game!