1) Yes it's in Weill. Good to hear that the piano is fuckin euphoric but um...the loudness will present itself as a...challenge, shall we say. Quiet piece demands quite the level of exactness and it's very hard to play on loud pianos. 2) I'm not playing the Nocturne, though I'll be learning it over winter vacation :) Honestly, I got the piece itself pretty easy, and while I will be the first person to admit that my technique sucks (no really, it does. Had a teacher from SFCM for the first 8 years of my piano playing and still my technique sucks) but apparently I'm musical enough to outweigh those flaws. It's all in the feeling :P I'll try and post a video of the submission I made to the competition that put me there.
About the loudness, don't worry! The hall may appear packed or even cramped when it's full, but somehow the acoustic space is vast and sound really travels. What I meant was that you can play very, very delicately (as you may need to) and it will still be audible for everyone in the back. I say that because I personally used to panic a bit about playing too softly or loudly during performances, whatever. The nocturne requires twice the patience, good luck ;)