1) the left arm. 2 kinects are 90 degrees or near to 180 I have the same issue of the model's left arm folding up oddly or failing to track at all even if it is visible clearly from both cameras depth mode. and it is almost always the the left arm. My model is an actress and her arms are bare. How do I increase accuracy? If I can get it dead on accurate I can use the model's hands thus solving the "no hand tracking" issue.

2) Sync slippage: Longer takes of over a minute often have the video sync slipping by more than an second. Both are set to the same time code of 29.97 frames per second. I imagine for most applications it would not matter much, but for this it is critical.

As for the limb issue, here is the problem. In Mocap studio, it does not see or loses track of the limb, you stop the tracking do back and fix it, refitting the pose does not work most of the time, and there is often a gimbal lock issue trying to pose the arm such that you are nearly doing this frame by frame. I can show screen grabs if you like.