This is exactly what I needed! After going through all the trouble to convert my F180S to E975 running 4.4.2 and getting it working right, I was really frustrated when I noticed the proximity sensor wasn't working.
The rubber gasket that surrounds the light/proximity sensors need to actually be reversed (So that the large hole is covering the smaller sensor)
There is a little nub on the rubber bit that is supposed to be there to make it fit one way, but the phone will go back together just fine with it reversed. (I guess you could take an exacto knife and cut the bit off if you want, I don't see why it would affect it.)
I did notice my screen goes a little wonky thought, after reversing the gasket, I don't know if it has anything to do with that, but it's like there's input when I'm not touching the screen. Might be nothing, but either way, I can live with it!
Thanks for the help!!!!