First you need dough without "springback" or else it'll keep bunching and you'll never get a nice thin crust. Solve that with a dough relaxer. That will give you a soft, easy dough that will roll smooth and stay thin.
Your free mix has dough relaxer in the mix. If you roll it thin, you'll get two or three pizzas from your mix.
Get the pizza roller for $2.00, regular $6.99!
Second, you need a pizza roller to roll out your thin crust right in the pan.