The changes were really minimal - the windway in V13 didn't fully "poke through" the mouthpiece on the sides, so I was thinking maybe the slicer was putting a layer or two of plastic there and mine wasn't by pure luck.
I also found the voicing window was slightly off-center from the windway exit, and corrected that. Not sure how it got knocked off center but I had 13 versions to do that so not really surprised I suppose :)
I've added the blender files to the main print page, but they are a little crazy.
The ones with "MERGE" have had all their boolean operations performed, to leave only the ocarina .
The ones without merge are the files I edit, then run all the boolean operations. Most of them are setup on the main ocarina piece, except for the last one (Boolean difference against the Voicing)
It was getting a little laggy having them all so I decided to leave one off. If you have questions on it let me know, it is really weird to look at.