Specifically, going through your comment: "moves", "external", "the very sense", "property", "freely caused", "prior thing".

It's important, I think, not to try to over-explain terminology. For example, all I mean by 'moves' is some relation that holds (by Will's premises) between God and a free action indirectly, and ourselves and a free action directly. Further specifying the meaning of this term would be distracting.

I think if you can make a specific case for the claim that some disagreement or argument is turning on an ambiguity, then we should stop and look over our language. Otherwise, I don't think it's generally productive to worry about terminology. We should rather focus on being understood, and I've got no reason to think Will doesn't understand me (and I don't think I misunderstand him).