Many bugs, never could imaging

First, an old talk, why those boulders or vases or any openable and destoryable small obstacls would stop player? what is the point of this desgning?

Second, I can't hit, even I'm so close to the enemy, running around it, but I Just Can't hit it?

And why an abyss ocurs in the boss room? I died because of so many monsters and I have no space?

:)