Hello! I just designed a dingbat font (all illustrations) and ran a test in Font Book in OS Maverics and it says "can not validate". I use FontLab 5.1.4 to generate. I don't have that problem when it's a letter font, only when I do an illustration one. It won't totally fine if you override and load it, no problems and computer still works fine. This problem does not exist on older OS versions.