I'm generating a .otf font from FontLab with a MetricsMachine .fea file I've imported. It works in the OpenType Preview panel as a feature, works fine, all kerning is present but when I generate an .otf for testing somehow the kerning isn't included (I've opened the generated .otf back into FontLab and it includes no kerning of any kind).
I'm used to generating .otf font files with FontLab group kerning which includes the OpenType kern feature, but this is different.
Any reason why this could be happening? The font has other OpenType features which should trigger the kern feature to work, and I've tried different Preference options like 'Export old-style non-OpenType "kern" table' and still nothing is working. No compiling errors either. Not sure why it's being so difficult.