Hi There.
I downloaded the latest firmware and now get the additional SETUP Activation screen for firm or cursor keys. I have set them for beep. Pressing the firm key light the screen but blank so that doesn't save battery life. I am interested that you set the lightsensor to the left. Does that stop the backlight coming on apart from pressing the contrast button?
I sent an email outlining this problem to the Philips Pronto team but have not had any reply yet.