I am using the yellow EVX-2 on my TXT. With the stock cans it works okay on 1 battery. I used a new female deans connecter and soldered on a shorting lead to the 2 terminals on it with a bit of 2.5 sq. mm flex wire (god knows what it is in awg, but its the same size as the wire on the evx-2 and my 4200mah batteries) and heat shrunk em.
Plug the shorter onto 1 of the esc's battery connecters, plug a battery onto the other one, switch on your transmitter (for some reason this is important), make sure the throttle trim is neutral, then press and hold down the on button on the evx.
One of 2 things can happen - 1. It switches on, the steering servo twitches, the green light comes on, angels sing, champagne falls from the heavens, etc.
2. Nothing. at all. In this case, disconnect the battery, swap the shorting plug to the OTHER battery lead on the esc, reconnect the battery to the lead that was shorted last time, press and hold down the button. Provided your transmitter is on, the reciever is plugged in to the right place.... it will work. If not, could be a stuffed evx :ack
Good luck..