Rdljr
Well then I take back what I said. The only time I ever saw something like that was when a friend used a zrester only on a winter trip and the little waffle patterns had water in them. So I'd change my comment to "you aren't using enough insulation under you". I'm also wondering if you could have rolled over onto moisture blown into the tent or if you got the top of your bag wet and then rolled over with it? Also it is very unusual to get frost inside a tent with the door open into the wind, sounds like there might have been a heavy dew as the temps dropped.
Jim