From a hardware standpoint, nose down and nose up are on the same axis, just half on one side, half on the other. The FoxVox Parser plugin automatically uses the range 0-45% for one side, and 65-100% for the other by default, leaving a small 10% dead-band in the middle (It may actually be 20%...I don't recall offhand).
I'm not familiar with the TM TARGET HID device, but you can manually set the desired axis range within FoxVox by clicking the controller button next to it and setting whatever range you want it to be.
For this command on the VCC, although the input is analog, it is working as a discrete on/off switch - toggling on and off as the axis enters and leaves the specified range.
