Thanks once again, this works! I guess I was looking in the wrong place:
http://chdk.wikia.com/wiki/CHDK_User_Manual . In the section User Menu - User Menu Enable - Edit:
To copy other menu-items to build your custom User Menu (Up to 10 entries)... Still in OSD parameters, select User Menu Enable [ Edit], now browse to any menu and select the item you want to add to the User Menu, then press +/- button or the equivalent button on the camera. The item has now been added to your User Menu.
Clearly this description is different, and the procedure given in CHDK_User_Manual does not work for me.
Gopal