Ok, thanks
For your problem, I think its because you havent installed the sound (‘sound’) library.
You can delete line 4(where i add the library) 11(where I load the sound) 69(thi should be an if statement) 70(where I play the sound), or download it.
I personally drew the ships and projectile sprites, while for the explosion sprite I took it from here(where I also took the sound effect).
Yeah, F is pretty akward, and for diagonal movement, I have this old topic
(I will add diag movement asaiantl (as soon as im not too lazy) )