If you are going to quote posts from another thread, it would be helpful to provide a link so others can see the full context.
This would be a useful feature, but just so you know, CHDK has no priority list.
FWIW, you can actually access the live view in lua already, using peek(). This is not convenient: you have to find the frame buffer address in the CHDK code (platform/<camera>/sub/<version>/lib.c), and decode the YUV yourself if needed, but it could be done.