I just did the application a few days ago. I fit about 5-10 decent size sentences into teh "special circumstances" section and it went through fine. As far as the essay goes, I amnot sure what the spacing rule is, but it took my single spaced essay fo a little more than 1 page.
NYU seems to have one of the better designed applications, so you can mess around with it how you want.
Hope this helps.
Actually, now that I think about it, does anyone else think that spacing would be a big deal on that application?
Thanks