Yeah I just saw that.
Visited your testsite, nice pictures, you're a "show" flyer or just happen to have flying capabilities? Wish I was
Exif is hell. I haven't dug into it that much but it seems tagnames are up to each and everyone. To be honest I'm happy it managed to get out your camera and the other stuff.
The tag the focal is relying on is named "FocalLengthIn35mmFilm", it might be the wrong one to take out. (Line 253 in the main script if your savvy).
I'll have to check some more info on this one.