All bmw paint chips and flakes like shit it seems its the one thing they don't invest well in is a good clear coat, my 2010 jet black hood and bumper are doing the same thing I'd give the car a good detail then Assess the state of the hood, personally I'd stay away from touch up paint it never looks good IMHO, I'd say clay bar the car then compound it, then wax with a good paste wax on her then,Finish it off with a real good paint sealer personally I only use chemical guy products on my car, there "Jet Seal 109" paint sealant is insanely good! And it last a year! It was made for NASA and airplane paints to be sealed with easy to use as well check them out!
http://www.chemicalguys.com/Chemical...wac_118_16.htm