Nothing happens on key-press?
I had the same problem.
I had to enable keyboard (and mouse) emulation for dos in my bios.
By default dos (that is in this case the command line interface that asks you to type a key) cannot communicate with usb devices.
In most bioses (at least on desktops) you can enable emulation for them to work under dos.
That did the trick when booting up for me.