If your rotors are on correctly you can access the star wheel from the access hole in the rotor. Use a flat head to push the star wheel. If your rotor is on incorrectly you will have to take the rotor off and then will see how the star wheel works.I need to adjust mine but it appears as this is different than any other PB I've ever dealt with. PB pads are good w/new rotors. Takes 12+ clicks before mine will lock the tires solid on a ~25* driveway. Do I start w/the handle adjustment? I have no idea how to do it inside the rotor/axle end of it.
I usually adjust till the drums stop the wheel from turning then back it off a couple clicks on the star wheel.