This is a new issue for me... I don't know when this happened, it's worked for me before. But when i'm customizing my opponents i can no longer change the race's super ability, whether it's a custom GC2 race, or a purely new race, i still can change it. The arrows click fine, but the ability doesn't change. I can change my own custom race's super ability in the player race screen, but can't change anyone's super ability in the opponents screen.