you take a voltmeter and put it at the ends of the wire you made and the voltage should correspond to whatever percentage you have set by the apex (i.e., 10% ramp should show 1v, 90% should show 9v). If you dont have a voltage showing, then you either have the wires mapped to the wrong Vx (specifically i think youre probably mapping to v1 instead of v2), or the wires aren't correctly connected inside the cat5 cable. After going through exactly what you are, next time i would just buy the dang cables from apex.