I'm applying some mocap, created with Rokoko and cleaned up in Motionbuilder, to CC3 characters. The problem is that CC3 characters, when exported using the MB preset and using mocap retargeted using the HIK skeleton, get a weird twist in their middle back. I suspect the problem is that the pelvis and hip bones in the CC3 exported character (vs. just the hip bone in the HIK skeleton) are doubling up the spine rotation. (I'm using the iClone_G5 STD Character-updated.xml file to characterize them in MB.)They are also very offset from the mocap skeleton.

I don't know if the problem is in the CC3, MB, or Rokoko skeleton, but the result is nasty.

In the pictures below the green skeleton is the one from mocap driving the animation. One pic shows the mid-back mesh twist I'm getting, and you can see how differently rotated the upper body is.

Thanks for any help!