[WR]虫姫さまふたりver1.5 ウルトラ アブノーマルレコ ALL 3999999999 

Not possible. There's so much planning involved with getting a route down so that you're not constantly getting walled off by bullets and killed, and being able to locate and destroy bullet-cancelling enemies at the right time to escape otherwise guaranteed deaths. It takes hundreds of hours of practice just to get the basic 1cc in this.

Nope. I think the actual hurtbox on those bullets is only a single pixel right in the middle, so you can squeeze right between them- I won't say easily, but not too difficult once you get to a point where this game doesn't feel impossible.