built in ban system to detect multiple accounts? sounds like you need another hack. im pretty sure they already exist.
i make no secrets about the potential exploits of all credit awards - look at the admin help for more details. the bottom line is that you will always need a minimum amount of moderation to ensure nobody is cheating. now, these arent programming exploits, but theres only so much i can do to validate each action short of making you, the admin, having to greenlight each transaction.
but at that point, why would you be using a hack to award points? just use a profile field :-p
ive given advice on what to look for and how best to police the more exploitable actions (such as multiple accounts, spamming)
i know youre all waiting, and im sorry; this has to be bug free if i want the next addons to be a success. thanks for your patience and understanding