Do you see the round CHDK icon and a red box with text showing version info - or just the red box and no round logo.
A round logo and red box with text that has version info, though it flashes by too quickly for me to read the whole text.
Do you mean pressing the movie button after you have started the camera ? Or does the camera start when you press the movie button ? Regardless of how you start the camera, you should see those OSD icons when you go to "shooting mode" (i.e. press the shutter button to extend the lens and get ready to shoot).
Movie button after starting the camera. To be exact, I start in playback mode (blue rect/arrow button), press Menu, do Firmware update, then press Movie to get CHDK display. They also display when I get to a shooting mode (lens extends) some other way, but before reading your post I'd only managed to do that by semi-random button pressing.
I now see that I also get to shooting mode by a half-press of the shutter button (hadn't tried that before, for some reason), and have the same CHDK display as in movie mode. Just doesn't seem to be any way to bring up CHDK's menus, or access most of the other functions. Most don't work as described in the manual, anyway.
More... Manual is the PDF of the CHDK User Quickstart Guide. Trying the functions on page 5, only these seem to do anything:
Half shutter + right does toggle the OSD display.
Half shutter + down (Disp) toggles the on-screen histogram (manual says it should be hs+up)
Now when I'm in still picture mode, quick presses of the Playback button toggle between shooting and display of pictures.
I did upgrade to the latest version (2023) from the autobuild site this afternoon (by unzipping the short version onto the card over the earlier full version), and all the comments above are from running that version. FYI it's ixus115_elph100hs-101c-1.1.0-2023_BETA.zip.