Hi hdbacks and all,
I'm a newb to CHDK but funnily enough did my first time lapse today, and worked out a way to turn off the LCD completely without a script.
Ive got the A720 IS so I cant vouch for other camera's but am assuming that most have a similar layout.
First press menu and turn REVIEW to off (think this has been said), then in shoot mode turn off the display (press DISP. twice), then press print/CHDK alt button to activate CDHK then just press your shutter and your away.
The obvious disadvantage is that you have to activate the script with a blank screen but its just two button clicks and I didnt need to see it whilst it was going on, I just shot it in auto, I had checked the exposure b4 hand and was just a test really.
Funnily enough I made a mistake when I did this first time round this morning, I forgot to set review off and ran the timelapse for around 3hrs 40 mins on a fully charge set, Uniross AA Ni-MH 2700mAh, and I still had 55% left and thats with review on,so who knows, you could maybe get to 8-10 hrs?