The Round Tower

Spoiler: Can B step off a half rotated stair?

Yes he can! Although there are many ways to get down to the water, one way is to lift one slider up to act as a block. Then with B on the rotated steps it will stop halfway between two points. With the steps at an angle to the grass blocks B can still go down them. Sometimes he's a bit reluctant but usually he can. Try it!

I really like your designs for the last two levels. Unfortunately, you have a lot of short cuts at the bottom (on the white field). To avoid shortcuts you just need to level up one floor! At the height of two floors, you will eliminate all the short cuts that can be made on the white field!
I really liked your non-standard move - cool!

My first win I bobbled the ball & lost it. Shoved B over win with the slider.
2nd round, all went as intended.

@MomoKeego you found a shortcut! I just tried it and won in seconds!