I'm not sure whether I'm missing anything, but I can report some extra findings from v1.1.1a, in case it's useful for anyone:
- the script from
http://chdk.setepontos.com/index.php?topic=10864 has allowed me to confirm a very short motion detection delay down to ca. 50-130 ms without any tweaking except for the trigger threshold, based on a 1080p/60fps YouTube video manually started on my smart TV*, and I can throw a drink coaster into the FoV and it will crisply snap it just inside the leading edge of the photo; still unknown how much further down the delay can be pushed, but I'm impressed for now, unless lightning proves I need even shorter delay
- after manually adding "111a" to v0.8 of
https://chdk.setepontos.com/index.php?topic=13956.0, the automatic power-down/power-on works as expected, and the script continues to pick back up after reloading CHDK, so at least that particular Lua script's native calls work as expected
- until I reinstalled to a freshly-formatted fat32 (for auto-boot), I had basically no flicker from anything (but disabled OSD); after reinstalling, there's a bit of flicker while the camera is being jostled about, but the menus are still perfectly usable during <ALT> mode while preparing for a shot
- there appears to be a *bug* when I change the <ALT> button to WiFi, because then the PlayBack button no longer functions at all; it's best to leave <ALT> set to PlayBack so that both modes can be activated via short- or long-press
*the TV's native refresh rate is 60 Hz and an ultra-slow-mo (16x @ 480fps) confirms that I can see time steps of ca. 16 ms matching both the TV's and video's 60fps