If you knew nothing about the situation I think it's actually a pretty decent movie..
They didn't explain a lot though, like how they processed credit card payments initially. Two coke heads didn't just magically accept payments one day high in a shithole apartment, you need a merchant account and/or a bank to process payments. They didn't explain any of that. They went from a buzzer attached to a shitty computer magically accepting CC payments to making 10s of millions.
HOWEVER, knowing the situation it is a difficult flick to sit though. Luke Wilson plays a trustworthy character with good intentions. When in reality Chris Mallick is a piece of fucking shit con-artist. So in that retrospect it makes you want to punch of babies.