Spoiler The most complex part in the logic puzzle, is also slightly unstable. I would have prefered a stabilizing grass block over the stairs that allow you to get on the level should you fall off. But a great complex puzzle once more! Enjoyed the challenge.
@Block builder Thanks for comment! Spoiler for that part, I'm intentionally leaving the placement of stairs at back like that. The purpose is for a trap or make someone who doesn't know the steps to go through it thinking as a dead end , although there is still another alternative.
@guihubux Are we talking about the same stairs? Spoiler I'm talking about the ball rolling off at the stairs at the front of the level.
@guihubux Spoiler Well, after much puzzling I managed to get the solution, only to find out that my ball push was very slightly at an angle, and the ball rolled off before R could step on the wall. If instead of stairs, there would be a grass block keeping the ball against the wall, it would be much more stable.
Finally solved. Great logic puzzle, thanks! Spoiler: Although... ...I didn't use the highest ball, and I didn't use any trick or exploit. Was it a red herring?
Simply brilliant !! It has been one of the most difficult challenges I have played lately !!! But I really enjoyed it !!! Excelent level of logic !!!...Thanks @guihubux