Won't the gearbox remap invalidate the warranty on the gearbox?
Also - Don't quite understand why you're in neutral at junctions? Is this where you've had the handbrake on and then on releasing it the car revs as it allows drive - or do you put the car into neutral? If the latter then wondering why people put it into neutral? As far as I know it's not advised by Nissan that you do this and surely just adds more wear?
My 09 gearbox gets pretty confused when going down into 1st gear fairly often and at low speeds isn't the last word in refinement, but doesn't 'kangaroo'?