ZBrushCentral

maya blendshape breaking

I need to sculpt a head in zbrush. I have a lorez head mesh in maya. The final mesh needs to have the poly count that is the same as smoothing this lo rez mesh two times in maya.
My problem is if i send the lo to zbrush and subdivide twice, then export this mesh to maya, it wont blend with the original low i smoothed twice in maya.

Do you know a way to work on a head sculpt in zbrush with lower levels so you can step up and down, and get that back into maya and get the blensdhape to work?

For now if i send a lo to zbrush, subdivide twice in zbrush, export top level to maya (in maya 2010 obj import multiple objects is = on)
in maya the top level from zbrush matches my low that i smoothed twice in maya exactly vert and faces, but it still wont blend between the maya smoothed and the zbrush smoothed.

So i tried sending a mesh to zbrush i smoothed twice in maya, then in zbrush reconstr subdiv to get lower levels. send the high back to maya, still won’t blend, explodes.

I’ve resorted to just sending the smoothed twice in maya mesh to zbrush and sculpting directly on the high. this blends, but im not able to sculpt on lower levels.

Thanks for any help,

Darrell