The Ball Tower!

Easy fun. Had to restart once to initially free up B. Nice design to cascade the balls at the start.

Thanks @Don G Rowe. Thanks for your comments!

Can't move B-bot out. One ball always blocks him.

@LittleIggy

Spoiler: Spoiler

there is a draggable just behind the wall where Bot is there. So just push it gently towards the Bot and the Ball before him will be removed!

D'oh! Thanks!