There are ways of bypaeeing the nats. First you need to know what noats syatem is fitted to your car.
nats 1 has the key fob (black with lock and unlock buttons)
nats 2 onwards will have a red or blue chip in the key by the key blade. (this syatem is very hard to bypass as it runs trough the ecu and control units)
on a micra K11 with nats 1, bepending on factory or accessory fitment, you can simply unplug the nats loom and control unit, and connect the origanal loom back in.
on a P10 primera, these where mostly factory fitted. again if you have the black fob with the 2 buttons, these can be bypassed quite easy. you will need to remove the glovebox and heater motor to gain exess to the nats control unit. ( located on the A pillar) when you disconnect the nats unit you will be left with the wiring loom connector. all you have to do is branch the coresponding wires with each other. and there you have disconected nats.
there was a adapter you could fit onto the loom when you had removed the nats control unit. dealers where surposed to return it to nissan as the adapter had a surcharge of £100.
i may have one laying around somewhere, i will look and see if i can upload a picture (if this forum lets pictures).
Any other nats system you will need to know electrics very well to bypass.
regards