Hi Martin,
You're correct that since there is not a specified "chord name" field in the standard MIDI format (SMF) filetype, that Composer does not always recognize chord names. I say "not always" because it does recognize and display the chord names for Yamaha PSR chord names, and will also edit them in a .not file. So, if you write your software such that the chord names you enter there are in the field that Yamaha uses, they should be recognized in Composer 2.6.3
Hope this is helpful
Sherry