Disposable 3

Not sure I solved it in the designed way with so many free blocks... Thanks!

Spoiler

I didn't touch the fixed draggable, just threw out the other three free blocks (after pushing the ball) and then walk with B to the win using the elevator...

Yeah that can work.

Spoiler

The fixed one is there to give you a more convenient way to dispose of the ball push sled. You can either use it or not.

@Don G Rowe - I found this one a little easier than your last in this series.

Spoiler: My way

I just knocked B off with the arm, walked over to the hidden stairs, removed the wall and hit the win.

@gmacpro Yeah. I've learned folks around here look at free draggables as a dare to find shortcuts, LOL. I'm still trying to tighten it up, and will post a redesign under the same title.

@nGord My initial concept was to have the player manipulate elements in the design, and then throw them away once they were not needed. The ending visual effect was hopefully a space cluttered with discarded elements pulled off the main stage platforms.
What I ended up with is a crash course in effectively employing free draggables. Which is great as I broaden my design horizons. Your input has been a key part of that lesson, and you've been nothing but courteous in teaching it,

Even with the free draggables, I liked this one the most. Loved the element the wall was hiding. After B reaches the ground and you move that last draggable to get him back up a level, the dark shadows left from the draggable obscured the easy route up so you wouldn't believe what I went through to get him back up to the main platform. When I revisited the level I finally saw, through the shadows, a much easier way to get B to the main platform.