The bikirom is a deluxe usb update daughterboard. It also has a built in consult port to derive some of its information and also allow full monitor/datalog. It has extra on board outputs to control various things, user definable.
It uses the factory nissan fueling algorithms and data, allows you to modify all of these in a handy environment.
So basically, tuning is the similar to those using eprom daughterboards in their ecu.
There is some nissan ka24 specific ecu tuning information here
http://eccs.hybridka.com . We are discussing info which would include the use of bikirom usb boards. The roms posted would work with those boards as well.