I'm preparing to submit a powerup, and have a question regarding "Will this Power-Up be free or paid Power-Up?" - in the beginning, the powerup will be free, but after some time when I get enough feedback and clients I'm going to make it paid, so I don't know a pricing structure yet. If I set it as free in the powerup submit form, will I have any problems in the future when I will be ready to make it paid?