Sorry, I couldn't find a way to get to a shell. Alt+F1 is the graphic installation screen, Alt+F2 is a black screen with a cursor, but I tried typing your command in and nothing happened. Alt+F3 is the log, and Alt+F4 (according to the graphinc install screen), is the kernel msg. All but F2 are labelled on the graphic install screen, actually. I tried others but they didn't do anything.