Oh, and by the way, this is in FontLab.

Third time's the charm: it's working now, but in a really strange way.

I had to add more features in the OT panel for it to preview correctly in the OT preview panel. After compiling, checking features, and saving, I re-open the font to find that the features have all been scrambled. The kern feature has been smashed into the liga feature definition.

Oddly enough, when I compile and test the fonts, they work! I've attached a picture of what my two (was three before I closed and opened the font) features look like. Strange stuff.

Alan

Adobe OT FDK + FL Mac (specially) have some problems with handling of line breaks on OT panels. There is a mixture of various kind and sometime, it happen

There is not perfect solution to that. Open the bad features file in text editor and compare to good features file and try to bring it back when its correct.

Alan -

I feel you on the election/OT blues. I've been sailing the same ship lately.

As I'm sure you know, this problem could be any number of things but
recently I've found that if I make even the slightest change to one
of my classes the OT code will jumble as in your screen grab.

Or, as JFP points, line breaks can cause the same thing. I've found
even extra spaces after lines of code can cause the jumbles.

Or, even a third, can be the voodoo of the "Add all glyph classes to OpenType
feature definition code" option under the Prefs panel. I might be insane
but I swear that things turns on and off by itself.

Hopefully some of this helps. When you get the features to work, save
the file in a guarded vault.

Thanks for the tips. It's just that I've never seen this happen before, so it caught me off guard.