Tower

I gave it a go and due to the hiddeness of the mechanism coupled with the obscure ball drop location, I gave up.

@gmacpro this level has the only point. Find the way

Spoiler

for a ball. You drop the ball down on a step. It will be blocked down. Than you stand on a stairs next to a ball and drop it to the left. Than you need to go with B into the position the ball can roll over Bs head to the right. Then you need to make a B to go through the point where the ball will stop in a center of the tower- before it drop there. So B will kick the ball out to the left. The last position is to protect the ball to fall out of the tower and hit it to the hole. The win block will go up

Spoiler: Video