not sure if anyone has answered you but yes you need to run the resistor pack and no the PFC does not have settings to chose what injectors you are running. the power FC only has different settings for air flow meters i belive. Z32 and normal plus others.
R32 gtst injectors are actualy higher in resistance than the GTR injectors and resistor pack combined but i wouldnt be worried about that, but even with a GTR power FC, GTR injectors without the extra resistance will damage the computer.
like i have mentioned before get yourself a resistor pack from a MR30 skyline. they are identical to GTR resistor packs resistance wise.
as far as the Power FC seeing bigger injectors goes it only ever sees injectors as duty cycle so it doesent matter if you have 1000cc or 200cc injectors it only cares about the duty cycle of that injectora and of course the impedence or resistance of that injector.
hope that clears some more questions up.