Well it says in the Release Notes for 8.0.1, that:
“When using the BCC 3D Objects category of effects, X/Y coordinate parameters do not display on screen point picker widgets – it is necessary to use the X and Y sliders to position things like Lights, etc.”
I think this makes it clear, that BorisFX has declared this as a known bug and I guess they will repair this in a coming update.
I also think that you are not using BCC 8 AVX for Avid MC6 or at least, not version 8.0.1
Is that correct?