Don't expect me to demonstrate how free will and causality can co-exist without invoking the supernatural that's fer damn sure!
By free wall as applied to people do you mean: "the partial freedom of the agent, in acts of conscious choice, from the determining compulsion of heredity, environment and circumstance"?
http://www.willdurant.com/glossary.htm
I take it you believe there will come a time when a new scientific theory supplants Quantum Theory, and the proposition of causation will once again reign supreme in the subatomic world, or are you only referring to the philosophical implications of Quantum Theory as applied to people?
Staying with the Quantum premise for a bit, assuming I built a thinking machine that used a random number generator to guide its actions, could that machine be in some sense considered to have free will?
How do you explain the individual's objective perceptions that a least to some degree, under certain circumstances, it appears to said induvual that at least in some sense, a decision was reached based on freedom of choice? Is it simply that the individual has neither the time nor ability to assess the underlying causation in its entirety? Is it hubris?
Do you see any difference between the free will arguments one might make as per the individual, and the free will arguments one might make as per mankind as a whole?