As I explained in PM, the code required for what you see in the video is not available in current CHDK. It is also not in CHDKDE. It is only in ewavrs version, which is discussed in the PTP thread you linked, and also on the PTP extension wiki:
http://chdk.wikia.com/wiki/PTP_ExtensionTo use this, you will have to implement the code from ewavrs version in your cameras. You can find that code from links in the wiki. If you don't want to use ewavrs chdkcam app, or want to change the protocol at all, you'll also need to write a client that can communicate over PTP.
It is my intention to add this functionality back into the main CHDK (along with a client library and application for the PC), but it will take some time.
