Grishka

abcm2ps doesn't comply completely with abc2.1 There's a list of differences on the home site: abcm2ps features. That being said, it does implpement most of the standard. (It's my standard program for printing; for posting tunes here, I mostly write the abc directly in a text editor and print to pdf for checking).

I haven't looked at the 2.1 standard in detail, but I did a lot of work on the draft 2.0 standard a few years ago (implementing a Prolog parser). There were still things I didn't like in 2.0 which I think are still in 2.1 (macro handling especially is primitive and limited in use). Many of the difficulties arise from pushing abc beyond what it does best - single line melodies - into the realm of general score writing (where I think wysiwyg programs are a far saner choice!). I'm not sure offhand if any of the software implements the full 2.1 standard.

Mick