Hi achillies 😀
Thanks for your reply! At the moment this is without any scripts selected (the camera is using a CHDK-enabled card, but just sitting in the standard record mode, with no CHDK menus active). However, I also have a script that's detailed in this thread:
http://www.rcgroups.com/forums/showthread.php?t=1387378
which looks for a 5V pulse on the USB pins of a certain length, then runs a simple 'shoot' sub-routine ... but even when using this, the performance is the same - it triggers to take the picture, then seems to wait for 4 seconds before taking me back to the record screen.
Under 'Show memory info' it says:
Free Memory: 378600 bytes
CHDK size: 281024 bytes
loaded at: 0x16EE30
Many thanks 😀
David