How do you adjust ADSR values of a virtual instrument?

Question

I'm trying to build a virtual instrument in wwise, and I want to affect the ADSR values (attack, delay, sustain, and release) of the notes that play.  I see in the RTPC tab that an envelope can be assigned to the X-axis of an RTPC graph that has all of the ADSR values that I need, but I'm not sure exactly how to apply it to my instrument.  The X-axis of the graph seems dependent on there being a Y-axis in the first place, but I don't want to affect any of the given Y-Axis options (e.g. Bypass Effect 0, Voice Pitch, etc.)  Is there a way to affect ADSR values without needing to use the RTPC graph or affect one of the Y-axis parameters?  Thank you!