You get one shot. Place the parts on the dashed pads, turn the launcher to choose which way it fires, and the ball does the rest — every target has to go down and the ball has to finish back on the launcher, inside its bounce budget. The ring round the launcher is that budget, emptying as it goes.
Some parts change when they are hit. A rotor turns a quarter after every strike, so the second time the ball meets it, it does something else. That is what stops this being a chain you can solve one leg at a time.
Parts change when they are hit — a rotor turns a quarter after every strike. That is the whole puzzle.