Hi, I'm Nathan.Sorry to hear that you're having trouble with this but I'll do my best to help you.
Take a look at this image, that foil type cover is what I was referring to
Do you see a paperclip icon here to attach images?
You also want to check that both connectors to the wifi board are in place, will look something like this: https://d3nevzfk7ii3be.cloudfront.net/igi/xcpZSaVcCJnkx6yM.huge
Those 2 snap on round connectors in the corner on your image are the ones to check and make sure they are good and tight.
It wouldn't hurt to open it back up and reseat all the connections just to be safe though.
Yes the 2 round connectors with the thick cables
Shouldn't need to redo the adheasive as long as your hands are clean and you're quick about it (don't let it be exposed for too long)
No problem at all, keep it open as long as needed.Nathan