Hi Cynthia, I found that the ridiculously strong glue Amazon used retained enough stickiness that I didn’t need to use any more. The battery is held in place by the design, and the black plate that you first removed is light enough that the residual glue held it nicely. but if not, some mild glue (not solvent based) should be sufficient.
Re: volume buttons, all of the back panel buttons (power, volume) and the USB port are run through the first cable that’s disconnected in step 5. If you are still having issues with volume once it’s been reconnected, perhaps check the alignment on the connector and make sure it’s fully seated. I’d also suggest not clipping the screen fully back in until you’ve tested everything; that way you don’t risk cracking the screen with repeated removals.
My battery too was bulging but once I replaced it, the device went back to it’s original flat profile so it doesn’t seem to have caused any long term damage.
Thanks for the instructions but there’s one important step that you missed for anyone trying this. I followed the instructions exactly but was left with a blank screen at the end of the reassembly. The reason for this is that when you remove the motherboard in step 12 (having removed the connectors from the top of the board), the action of removal also disconnects the display and digitiser connectors which reside beneath the board.
This isn’t explicitly mentioned in the instructions but if you look to the right of the images for step 12, beneath the right hand corner of the board is a small black connector on a copper coloured square and a little further back from this (obscured by the board in the picture) is another larger connector. Both of these MUST be reconnected when replacing the board and before continuing the other reassembly steps otherwise your screen will simply not function
Hope this helps someone.