John, I think Your assumption about the MusicT_EX programs is correct, the program abc2mtex has not been updated since the lyrics feature was added to ABC notation. I don't think the lyrics would make it through the translation.

I have taken another look at the GNU LilyPond program that Murray first told us about in 1998. That package includes a program (abc2ly) that converts from ABC to LilyPond notation and may include conversion of lyrics as well. LilyPond support lyrics and, unlike Walshaw's early translation program, is still in active development.

      - Mark