Regardless of the thumb default setting, this brand new hand is completely unreliable regarding thumb rotation. For an 80'000 CHF item, the amount of failure and absent reliability is refreshingly surprising. The hand is completely lovable. But it never seems to deliver on grip, or, being there (as a hand, that is) when one would want it to be there.
That is how the thumb program really looks like. The thumb rotate program never exits reliably after 2,5 seconds.
The software contains a short description of how that thumb rotator should operate. Pure fiction there.