Thanks for your comment!
I don't get your comment on the UI icons. You have UI on the bottom for that. And when a bonus that you want is selected on the UI you should press ctrl to actually get this bonus (this is a Gradius-like game).
Regarding the bosses, they actually have phases (end of level 1 has 2 phases and end of level 2 has 3 phases), what you met is a mid-boss (which should be fast to beat if you use the bonus).
