There are literally 3 different NB4/RX packages you can get depending on the vender. Amain usually sells the "mini z" RX setup, HobbyKing usually sells the setup that includes 2xFGr4S and Amazon/Banggood/Hobbymate/Everyone else sells the package that includes 1xFGr4S and 1xFGr4 V2.

As far as binding, make sure the RX is running, at minimum, firmware 2.0.93. You can use/download Flysky's stand alone RX updater which makes the process easier. Beginning from firmware 2.0.93, you no longer NEED to update the RX firmware after updating the radio firmware.

Also note that when running in "1 Way Mode" you'll get zero feedback as to whether your bind was successful. I've seen people make the mistake of thinking their bind has failed because they didn't get telemetry feedback telling them that the radio/RX is bound when running in this mode. "1 Way Mode" is just that, one way communication between the radio/RX for the added latency bump. "2 Way, 2 Channel" mode is shockingly fast and is very noticeable from "2 Way, 4 Channel" mode.