Very nice write up. I had bought a lightning adapter to do the same thing, but when I went to test it before installing everything it wouldn't charge so I returned the adapter. But I'm sure I was over 80% charge, so maybe that was my problem.
What year is your car?
2010 E90 335i Black Sapphire
COBB/PTF proTUNE/Alpina/BMS Drop-in/PSS/Blizzak
Best Stock 1/4 time = 14.1 @ 99.4 at Bandimere Speedway (DA = 7,400ft ASL; 13.5 @ 103 corrected)