My method for making tails in Moho/Anime Studio. The same technique works for hair strands and other flowing elements in your animation. squarebearstudio.com
I'm not sure, unless the smart bone isn't on the same bone layer as the arm bones. You can't parent a bone to a bone on another layer, you'd need to bind the layer to the bone. Otherwise, I can'th think of a reason you couldn't parent a hand bone to the forearm bone.
think about joining our group, it's a great place to share your work and to ask questions. There are many people who can help, plus you can share videos and screenshots of any problems: facebook.com/groups/mohocharacteranimators/
You cannot parent a bone to a bone on a different layer. You would need to parent the the second bone layer to the arm bone, and that would mean setting the origin of the hand bone layer to where it should rotate (the wrist).
