My company uses a number of custom fonts that contain various icons. All of these icons display correctly in the FM client and when using the "Print" script step, but some of them disappear when using "Save Records as PDF" on a Mac. I'm attaching a screenshot that demonstrates this with a test font and example file that I'm attaching to this discussion.
In addition, when the first glyph on a line isn't rendered, the entire line isn't rendered. (See examples 3 and 5 in the screenshot.)
At first glance, this seems to be an issue with glyphs in the Supplemental Private Use Areas (unicode ranges U+F0000..U+FFFFD and U+100000..U+10FFFD). Glyphs in the original Private Use Area (U+E000..U+F8FF) seem to save to PDF without disappearing.
This problem didn't exist in FileMaker Pro Advanced 13. It does appear in FMPA14 and FMPA15. I have only tested this on Mac.
Please let me know if I can provide any other information.