How the Ending Works : check the onCollide script menu of the block that get hit at the ending. You will see it wrote (e)=>{groovyon}. It activates the groovy feature of Algodoo/Phun. To deactivate it, go to the console menu by pressing F10, then type in groovyoff, press Enter.
It's almost cheat-safe but you can cheat by pause the sim, take the drag tool then drag your checker then start the sim when dragging, kick all green checkers.