As per the solutions recommended here regarding my issues with elbow positioning, I have implemented a solution of an arm: upArm, loArm, hand, and upIK (shoulder) and loIK (wrist) IK solvers. The loIK bone is used to position gross movements of the arm and upIK is then rotated to roll the upper arm so that more exacting positions are possible.
First, I’d like to express my thanks to everyone at elYsiun for helping me. This is a complicated arm with a steep learning curve, and is very capable.
Positioning the elbow via rotating the upper arm via rotation of the bone is an exacting science. An idea is to attach a handle (null bone) to the elbow so that it can be positioned by G-rabbing and moving the handle.
Is this a good idea? I think I should focus my energy on first learning the many possiblities of this new structure.