Just tried it on my brand new kobo Aura, works fine (with and without light on,which can still be adjusted).Just be careful to get the
kobo-nightmode_build13.zip
because other builds won't work for firmare 3.3
from france for this great trick
(I was just a little confused upon installing, because the installer and uninstaller folders each have a file named KoboRoot.tgz, and it wasn't very clear to me which one to use (or both?),anyway, the one to go for is in the "installer one",and the other one is to remove nightmode (I would just have deleted it from the kobo. folder, but I guess that wouldn't be advisable)