If you find that your face doesn't change when you've updated the save file then try starting Steam in off-line mode so that the steam cloud doesn't try to overwrite your save with it's saved version.
I've also added an option to save a hex dump of the facegen data to a text file for cut and pasting into FONVEdit.
You can download it from http://www.oblation.eu/downloads/FaceGenExchange0-4.zip.