You may need to create your control panel layout first (using the 'panel designer' mode) if they didn't provide a .cpl file. If it's not 'seeing' the .ipc file you might still be in panel designer mode and not in 'key assignments' mode so when you click 'open' it is searching for .cpl files, not .ipc files.
Oh, and be sure before you click 'program' once you're ready, that you set the 'download timer' to 10 seconds in the options.