ZBrushCentral

Help! Zbrush rigging problem (too high polygons,rigging fingers wrist elbow together)

Hi! I have a few questions about Zbrush rigging.

I got my model which is bind meshed. I got all red sphere from skull to tip of each fingers and toes.

the problem is…when I tried to lift up its arm, (let’s say I grab its wrist and then pull it up) then its hands and fingers are not moving and screwed the shape. you know what I mean??

what should I do??

and 2nd question is that I have model which has 12sub tools petty much high poly…total 700k polygons. I found I can simply use Zplugin - Tpose mesh to apply rigging. but it’s still too high and my pc almost get crashed everytime I pick red sphere and move.

unfortunately, I deleted all my low res while modeling. what do i do to get smooth rigging…???