I’m gonna be that guy: Not entirely true, since the opening of the sleeve is below the rotational axes. Therefore you need surge and sway to compensate for that movement to truly have the opening stay at place. It will depend on the software though. I don’t know whether or not there is linear compensation for linear deviations from rotational movements.
Indeed they are.
Have you tried with OpenFunscripter - a scripting tool - 3.2.0 release ? I think OFS is always worth a try. If you want to have a circular movement, make sure roll and pitch are shifted, s.t. where one is at maximum, the other is at 50% like a sine and cosine:
Like so:
Or if you want to smooth it more to look like a real sine and therefore a smoother circle:
