Ok, so I put the 1.01c on it and loaded it using the manual mode (having to go through the firmware update to turn it on) and I got the splash screen (it was up for too short of a time to tell exactly what it said), and now I've got what I assume to be my open memory (962M) the always own battery display with percentage, the time, and "opt:28°". I haven't discovered any other differences yet (not in the menus or function).
A short press in the video button will take you into <Alt> mode, you'll see <Alt> bottom center of screen.
Then press "Menu", and you're in the CHDK menu.
Then, you'll probably want to
read(on the web) or
download(as pdf) the User Manual/Guide ...
enjoy,
wim
[edit: spelling + added some more text]
PS To increase your comfort and decrease power consumption while playing with the CHDK menu, I would
also recommend switching to REVIEW mode before switching to <Alt> mode. To do this,
press
and hold the 'Play' (=blue triangle) button until the cam starts retracting the lens assembly.
Note While in <Alt> mode, all keys are hijacked by CHDK, e.g. you can not take pictures; to
use the cam 'normally', leave <Alt> mode with another short press on video button (CHDK will
keep running in the background)