It works, the autofocus lamp turns on! (note to testers, don't turn the camera on with the autofocus lamp aiming directly to your eyes! Ouch!)
I tested turning the camera on with the PLAY button and the ON/OFF buton, and in the 3 shooting modes (auto, program and video), 6 combinations total. Every time, the only thing that happens is that the autofocus lamp turns on. No reaction on the other LEDs or the LCD. The camera freezes with the lamp on, and must remove battery to reset.
Like you said, the only way to run the code it to have the card bootable and locked. Otherwise, the "upgrade firmware" option is abscent.