Well, as it turns out the repair shop didn't try at all! I figured since I couldn't make it any worse I'd dis- & reassemble the phone (following this tutorial: http://www.youtube.com/watch?v=i9u7r4j0atU). Put it back together and turned it on: works like a charm! Guess the trick was disconnecting the battery for a while, which obviously the shop didn't even try. Good thing they didn't charge me. Well, good luck to everyone replacing their screens. If I can do it, everybody can!