My home button was extremely loose when installed in this fashion. To help remedy it, I installed the gasket sandwiched between the button and glass instead of on the rear face of the button. Not perfect, but a much better feel. Prior to that, the button actually stuck out further than the glass.
I have the same problem, I assume. The bracket didn't seem to sit flat when mounting to the screen, and now the home button wobbles.
The blue film would NOT remove from my strips. It was permanently adhered to the strips. I now wonder if the manufacturer messed up and put the blue film on upside down.