open sesame

I still don't know how to post an enlarged QR-code

The slider under the jail has no other purpose than to unblock the mechanism under the ball, in case it blocks. I don't know why, but sliding mechanisms block sometimes.
You can see when it blocks through the cilinder on the edge (same for the finish btw, bt no unblocker there)
If it blocks, just knock the slider against the mechanism (it won't actually move btw)

@Sculron

Spoiler

simple ways to enlarge QR code is try to add different water levels or name your level card short as possible this works some times hope this will help you.

@Sculron Upload an official card (not any picture with a QR) here: https://mekostudio.com/customizer
Check "Optimize the size of original QR code on the card" and hit generate.

As to the level, did you misplace a wedge after the hercules move?

Ah nvm, something hidden and delayed...

Forgiving the hidden thing, and the fact the second ball-push mechanism jammed once, I can rate this a 5-. Again some nice steps in the solution, quite enjoyable.

Similar to “Gate” but still very enjoyable and worked smoothly for me. I liked the reappearance.

@Block builder the delay is intentional
Maybe I should have given a hint about this, sorry

Apparantly a hint is required, so here it is

Spoiler: hint

After the hercules move, B has nowhere to go... or so it seems. When you push the gate with R to get him through, a mechanism is activated to open the gate for B. The gate should open by the time R reaches B's gate

just in case, here's another hint

Spoiler: hint 2

When R pushes the ball to let B get to him, B can get to the last 2 balls, but R seems blocked. When R stands on the draggable (where he pushes the ball) slide that draggable and R falls down. He will reappear at the stairs

and finally

Spoiler: hint 3

After you push the two balls, the finish should appear, but B can't reach it. R can, with a little help

Very nice and original level were Alibaba B had to solve interesting steps, thanks!

WOW!! A MUST !! Excellent cooperation/logic level....Very fun gameplay and challenging!!Thanks for sharing and great job @Sculron

I needed the hints but they didn't help as the 1st ball didn't release B. Restarted and on the 2nd attempt, the release occurred. One of the hints came in handy then. Thanks

@gmacpro my first comment refers to that issue. For some reason, underground sliders tend to block sometimes, for no logical reason. I've had this happening with other people's levels too, while on second try, they work perfectly.

Nice progressive level with some interesting steps, as BB said mechanism blocks some times but works mostly, thanks!