I was wondering why builtin Canon menu was so slow under control of CHDK, and I think I've found a bug in boot.c in line 76. After changing this line to instruction found in firmware, menu is working as fast as without CHDK.
In addition I am now able to:
- boot camera in capture mode (hold power button until camera is started)
- switch to playback mode (even with photos on card) and back
- take a photo