Thanks for the detailed reply, Tim. I figured the explanation would be something like what you've said. I hope having my big Junicode files will help you find solutions. It may be that there are better ways of coping than what I've done (marking big blocks of glyphs "no kerning," so that, ...

I marked about 750 more glyphs "no kerning" and succeeded in running KO overnight.

So far I've used Kern On for two fonts. I'm getting used to its ways, and I've got to say I really love it. One font has seven masters and 1368 glyphs, while the other has six masters and 4865 glyphs. With the first, when KO runs, it finishes in under an hour. With the second, well, I started it bef...

Thanks for the reply, Tim. The files are in Glyphs 2 format, but being edited in Glyphs 3 (because Glyphs 2 files work better with fontmake). You can grab either Elstob.glyphs or Elstob-Italic.glyphs at https://github.com/psb1558/Elstob-font/tree/master/sources. Look especially at glyphs b.lf, h.lf,...

First of all, thanks for this amazing tool, and for this useful forum! I've read this thread and watched the "Under the Hood" video, and I'm having problems with KO not finding a number of glyphs referenced in OT features. The feature that's giving trouble (the one I've found so far, anywa...