Simple to do with the legacy remote.
1st- put in engine into the program mode by manually taking switch from run to program. Power up track and program what id # you want to use for that number under ENG, # 1 to 99, and press set on remote. Whistle or horn will sound( means it accepted that number which can be changed anytime to another id #).
2nd- turn off track power and put engine back into run mode switch manually. Power up track, ENG id and touch horn, whistle, aux 1 button so you are "talking" to that engine. Then press INFO button on remote and slowly turn the red dial and look for the prompts for what your engine is, steam, diesel, etc and press the button directly below and proceed on turning the red dial untill you see Legacy, press the button directly below. Do the same for sounds until you see Legacy sounds and press the button directly below that prompt.
I believe if you press info again, it brings you back to the main operating screen. As for adding the cab # of the engine and adding what you want to name that engine, it takes a little more explanation, but that will get you operating.