I leave tomorrow, so I can update you when I get there (assuming I get wifi somewhere). Otherwise, I hope someone else helps you. We've gone twice (this will be #3) the last week of Sept, and never had a problem with crowds. We've done RnR 7 times in a row, waiting only for the pre-show, to give you an indication. Also, I've never been to WDW when it was raining, so if this upcoming week is bad, it will be the first for us.