hey haven`t wrote something in ages but here i can help you i would suggest changing you default renderer to nvidia mental ray , done with that ? place a standart omni light in you scene select the proper channel for your maping (from waht i can see you already did) expand you cage a little by using the % slider ; dont worry it will always " reset" to 0 when you let go. For the future you might be interested in Floating geometry (< googel ) for parts like this. If all fails (even if it works ) you might also be interested in a little tool called XNormal as far as i'm concerned the one and only map baking tool out there. also 2k for a normal map is pretty heavy it might look nice and shiny but in the end it will only lower Performance (with proper antialiasing a 512 Normalmap should do the trick ) hope i could help if there are any spelling mistakes, i`m sorry might be the wine going over the whole thing an omni light !!might!! not fix the issue, if it does never mind ( ;( dammm XNormal should though)