When setting up developer mode last night, I was getting the yellow exclamation mark with a warning message saying something like "Chrome OS missing or damaged"
I've learned that this is a message intended to scare off casual users, but you are supposed to hit ctrl + d to bypass it.
I got as far as installing crouton, and then unity (which was my mistake because I read that the Asus Flip chip cannot handle that skin).
Unsure of how to "unistall" it I also learned you can install multiple "chroots" so I added kde, but then deciding how to start it up up got confusing so I powerwashed the chromebook and might give it a go again later today.
Loving the chromebook so far, but really wishing the desktop publishing capabilities were stronger. Microsoft online does not give me some simple graphics manipulation that a PC would for Word & Powerpoint docs. Hoping crouton/ubuntu solves that.