Hi there!
I am new registered and found interesting stuff here @Hisymak
in terms of genmidi editor there is an alternative to edit *.op2 Files -> the imfcreator, maybe this is still unknown to you http://www.shikadi.net/keenwiki/IMF_Creator
or even more extensive -> the OPL 3 Bank Editor which allow import und export many 2-operator, pseudo-4-operator, and 4-operator instruments and banks
http://www.shikadi.net/moddingwiki/OPL3_Bank_Editor