1. Either Get Poser 8, because the (new) MorphTool can smooth across joints.

2. Or better wait for colorcurvature to finish his morphing script.
   It allows you to export a welded AND posed figure, fix the joints in a dedicated modelling programm, then simply reload the fixed figure again as a morph target into Poser.

It's absolutely brilliant !

BTW, K1 actually IS the worst rigged figure that DAZ has ever issued.
Even the slightest scaling immediately breaks the joints.
So good luck trying to fix it. ;-)