Thanks for trying out the new version!
Just a moment ago, I had to patch the game again because Godot has this REALLY annoying quirk where, if you have it export only specifically-marked resources (which I do sometimes to not export unused assets and make the file size smaller) Godot will not have newly-made assets marked so it's really easy to export a new version with the new mechanics and art you add not being exported at all. And it's weird because I could have SWORN I manually marked the new assets so I don't know what happened.
I noticed when messing with the game that the boss wasn't even shooting projectiles I made. So that and the new signals should be working as intended now