[NFiftyWon]

So i am going to be doing a 75 Wet shot on my N51 via Nitrous Express Proton Plus Series (EFI Fly-by-wire). I have most of the parts but there are a couple of things that remain unanswered after correspondence with NX, and after reading the 3 or so threads on here from people who have done nitrous builds.
The First thing is, NX recommends going 2 steps colder on plugs and spacing 0.35. I was told after asking how to find the plugs/ asking them for a part number to just go 2 numbers lower on the part number from OEM. according to a user on another thread here, they recommended NGK LZFR6AP11GS, which also appears to be the OE part number? After looking around on ECS and Turner not only was i unable to find a plug that seems 'colder', but they are Platinum which NX recommends against using. So any information on that would be helpful. I was also offered up by NX that i should be able to tap into a fuel pressure test line, but i couldnt find it.. a local guy said i was going to have to splice the line with a T fitting.
I also read on here the easiest way to wire to the engine bay was to follow the battery line, however, NX strongly recommends braiding/pairing the line near a positive wire.
Most of the builds i have seen on BMW the jet is drilled and fitted into the side of the airbox by the filter, NX also has fittings that would support this, I have a Injen Nanoweb CAI and some nitrous guys told me the jet wouldnt hold and would fly off, that i needed to have a custom flange made. The guys on here also did not do any tuning to my knowledge, but NX is recommending pulling out 2 degrees of timing.
Guidance here would be rather appreciated, this is my first Nitrous setup and getting conflicting information isn't really making this any easier. Ha

On a side note, i was planning on getting the StageFP/BPC tune in the near future. I would assume this would involve advancing the timing, do you think this will be a problem? And if so do you think there would be any willingness on their end to make adjustments to the tune to allow for nitrous? Or would i be better off dyno-tuning somewhere local?