If the phone isn't turning on, how do you get a insert correct sim error???
It is ok if you get the insert correct sim error after flashing, and the phone is working. But YOU NEED to customize your phone. Don't waste your time to unlock it until you have put a custom pack.
About bytes mismatch error: Probably you(or anyone else) tried to apply the quick access patch before. So if you get a mismatch error just press yes to continue the operation. And FOLLOW CAREFULLY the tutorial on first post of this page.