Aionios, your doctrine of causation is inconsistent with Christianity.

That's not, however, because Christianity is at war with science in general. It does, however, propose the reality of miracles, specifically, the creation of the phenomenal universe (whether or not limited to the products of the big bang), the miracles done by Jesus and some prophets and saints, and, something often overlooked, the miracle of counselling by the holy spirit. The last is a very significant miracle, because it consists of non-spacetime complexity, let's say, that may or may not manifest as spacetime information (subject to Shannon equations - http://en.wikipedia.org/wiki/Information_theory - thermodynamics, etc.). To appreciate the scientific significance of Christians claiming they may, through grace, receive insight or other information from the Counsellor, the holy spirit, you can also review this pair of Wikipedia paragraphs.

"In 2003, J. D. Bekenstein claimed there is a growing trend in physics to define the physical world as being made of information itself (and thus information is defined in this way) (see Digital physics). Information has a well defined meaning in physics. Examples of this include the phenomenon of quantum entanglement where particles can interact without reference to their separation or the speed of light. Information itself cannot travel faster than light even if the information is transmitted indirectly. This could lead to the fact that all attempts at physically observing a particle with an "entangled" relationship to another are slowed down, even though the particles are not connected in any other way other than by the information they carry.

Another link is demonstrated by the Maxwell's demon thought experiment. In this experiment, a direct relationship between information and another physical property, entropy, is demonstrated. A consequence is that it is impossible to destroy information without increasing the entropy of a system; in practical terms this often means generating heat. Another, more philosophical, outcome is that information could be thought of as interchangeable with energy. Thus, in the study of logic gates, the theoretical lower bound of thermal energy released by an AND gate is higher than for the NOT gate (because information is destroyed in an AND gate and simply converted in a NOT gate). Physical information is of particular importance in the theory of quantum computers."

The most free version of our free will, I would say, lies in our miraculous ability to accept or decline these newly created quanta of the universe, bits of spiritually derived information. As bigcalv correctly notes in his baptist-pentecostal lexicon, we get to choose whom we will serve.

If you think this is madness, then you need to be consistent and claim that all apparent spiritual insight is just the mind apple-falling within itself as triggered by apple-falls of attraction to apparent spirituality. In that case, though, your very claim about this subject is just an undistinguished moment of apple-falling and can be discounted as a thermodynamic reflex of some kind.

But would I claim that atheists, then, have no free will other than that which allows them to choose to be atheists or not? Apart from any spiritual free will, there is a lower approximation that certainly feels like free will, and you can feel one variant of it yourself, if you think about how you make trivial decisions in moments of calm. Let's say it's whether to wash the dishes or the clothes one sunny afternoon when neither is particularly urgent. You need to make a more or less arbitary decision about that; but also, since you don't need to decide instantly and can mull about it for awhile, you need to decide whether or not the moment has come to decide. In other words, you need to decide to decide. But in order to do that, you must resolve to make this decision about timing, and thus you need to decide to decide to decide. Actually, logically, this cascade upward into decision-regress continues ad infinitum, or at least it would, except that the human brain can only deal with about 7 or so of these regress loops, since they occupy the same part of temporary memory that is used by things like telephone numbers. The study you mention where people seem to have decided before they know they have (you could cite Malcolm Gladwell's Blink as a general reference for this sort of thing) is only the beginning of what goes into a decision that isn't circumstantially forced.

So unless your mom comes along, boots you, and says, "wash the dishes," you need to resolve your decision-regress about what, when and how to decide, using some sort of brute fiat. Maybe it just relates to how many regress loops your mind can stand to contemplate. At some point, though, there is what you might call, philosophically, in your vocabulary, "the moment of 'fuck it'" when the decision emanates in full form and you head for your laundry bag.

One thing you can say about apples falling from trees is that they don't have to go through deciding to decide to decide to decide to decide to fall.

In case you do prefer to resort to randomness in the brain, though, rather than arbitrative regress alone, there is no shortage of it. Apart from any quantum randomness, if you look at the brain in the microscope you will see that it is an ocean of Brownian motion, which is as random as things get. Every molecule that goes into solution there, including all your neurotransmitters, is banging around randomly like a 5 year old in a room full of candy.

Science is not simple and it's often inconvenient to simple arguments.