Two things to check before you send it off.
If you've had the hand off of the trigger to stone it (which I wouldn't do anyway), does the hand have spring tension on it? i.e. when you move the hand while it is installed on the trigger, does it spring back and forth, or is it just loose? If no spring tension, then the hand has to be put back under the little hand spring within the trigger. Easy to do but hard to explain.
Second, check to see of the hand pins are not bent. If not straight, this could be a problem as well. If not straight, easily straighten them back to perpendicular. I say easy, cause you could break one of them off, especially the littler one.
Good luck