Get the original firmware from the usual places and inject the key into it. Flash the original firmware onto your Benq. Make the necessary dashboard updates (xbox 360). Re-flash your Benq with LT+3.0. Of course, this is all done with JungleFlasher. Depending on how old your dashboard is you will need "pre" or "post" firmware. I can't remember the specific dashboard version but you can google that.