I'm not sure if this answers all of your question, but I do know about the flicker issue. It's only happened to me a few times on a glass repair, but it frequently happens after I fully disassemble a phone, motherboard and all. Still don't know what causes it, but I do not how to fix it. All you need to do is a image burn the LCD a little, to do this, turn the brightness all the way down and set the phone to never lock. Put it on a charger and let it sit there with the screen on for anywhere from 30min-4hrs or so. When you turn the birhgtness back up at the end, the flicker should be gone. Some of them are a bit stubborn and you will have the increase the brightness is small amounts at regular intervals. Regardless, this method works 100% of the time for me. Let me know if it works for you