I don't get this one.
To pick up the rainbow stars, I have to push a blue ball.
I saw the level in the editor, so all next is in a spoiler.
When I picked up all stars, I must be at the white gate on the left.
But the blue ball behind the fake walls and trees in the south, has stopped.
So that ball will not roll back over the white buttons.
I think I never can make it to the white gate before the blue ball stops on the right side.
Or you have to put a convoyer to the left on the right side when the ball has to roll back.
Can you help me out please?
I've done the other 2. It's fun too.