[saljam]

Does this have notation for quarter tones? I can't find that on their website.

That's always been a pain point for me. No quarter tone notation rules out a lot, including most of Arabic and Turkish, and much of Greek maqam music.

[colomon]

Dunno about OMN, but Lilypond seems to have quarter tone support: http://www.lilypond.org/doc/v2.19/Documentation/notation-big... (third staff down)