So I just bought this game. I want to play it, but this mode just locks up when I choose my character. None of the buttons work at all and I'm just stuck on that screen until I alt+f4. The challenge mode works fine, though. Any solution to this?

as title

Great little game, but the story is completely losted on me because I cannot understand the language! The english translation is, sadly, poorly done and native speakers cannot follow the story much at all. It is short enough, if you reach out to me, I am happy to help you rewrite the translation so that it is more coherent. I would be a shame to release the game in this state, when it shines in so many areas....

I have no idea how to beat this mission. It doesn't seem that there is enough time to beat the mission and the boss constantly keeps moving off-screen.

I feel its too difficult. What weapon do you use ? I lost at stage 5. Any tips ?