You raise a profound question indeed, Dennis and from my limited understanding I can only venture a tentative reaction.
Perhaps ‘potential’ and ‘actual’ are not adequate terms to qualify prehension, if you take ANW serious that only actual entities are fully real, as you state. What actual occasions ingress are ‘stubborn matters of fact’ and not actual entities.
Potentiality only enters with the creativity of eternal objects. If I understand that correctly, the traditional opposition of potential and actual is moot in philosophy of organism.
But that does not address your issues with selection and the lack of direct experience.