The first step was to fool the electronics into thinking the lamp is present so that the projector will start operating properly and get rid of that automatic shutdown. A few Google days later I came across a French site on the very same subject. It turned out all I had to do was to find a logic signal that was up (5V) during the first two minutes and down (GND) just before the LED missing indicator turned on. I found it eventually, using my multimeter. By pulling this signal up (a simple wire jumper connected to a 5V source I found on the board) it started normally thinking the lamp was present and on. I connected a laptop to it and checked that the movie was playing by looking into the lens while holding the same flashlight inside the projector. Yes! I was glad I did this, I’m not that experienced in electronics and I feared I may end up stuck at this stage.