i've tried everything, followed the iclarified tutorial to a T. i've shift+restore in itunes and restored my phone to a custom 3.0 FW ipsw. then i ran redsn0w and followed every direction, and after i click finish, my phone shuts off, but doesn't reboot back up, so i turn it on and i am still at the no sim enter a valid sim to activate this phone screen. i've restored and ran redsn0w 3 times. can someone with patience please help me?