Great job on the site. Looks great.
I have not really experimented much with revolution slider in this area but can provide some hints on how to proceed. I am interested in knowing if you are able to resolve this since we are planning to do something similar in our upcoming theme. Will update you if we get to this on our side.
Here is how I would proceed presently using API exposed by the revolution slider and the jquery appear plugin included with Appdev –
/* Pause the slider on load */
revapi2bind("revolution.slide.onloaded",function (e) {
revapi2.revpause();
});
/* On Scroll resume the slider */
$('#rev_slider_2_2_wrapper').appear();
$('#rev_slider_2_2_wrapper').on('appear', function () {
revapi2.revresume();
});