Hi Aard, I'm sorry if you've answered this question a bunch of times but is getting the Left and Right controllers for flexes only possible through .vta and not through .dmx files?
It's possible, but it's not nearly as simple as it is in VTA. How it's implemented is up to the DMX tool developer. Game Zombie's DMX tools for 3dsmax, for example, requires you to paint the left and right sides with vertex painting. I don't know what process the DMX tools for Blender involves.