Thanks, Mick. I found out about octave=-2 myself, but I am still somewhat puzzeled about versions. I remember that using Concertina.net was discouraged at Mudcat, presumably because of such problems. It seems that mandolintab.net is our best bet; Mudcat may declare its behaviour the Mudcat Standard, for the time being. This thread is called "Mudcat ABC Tune Guide", so it is the right place for such declarations by authorized personnel (not by me). Of course we may run into problems if mandolintab updates to an incompatible software version.

I personally don't have any problems with printing my own music correctly, but if I post some ABC to Mudcat or elsewhere, I would like all its printouts, conversions to MusicXML, etc. to be equivalent, with any from a sufficiently long list of "good" software, and forever. (If necessary, I can live with a list of features to be avoided because of uncertain compatibility, similar to the one from abcm2ps against ABC 2.1.) Am I asking too much? Can we hope for such lists, if not from abcnotation.com, then from the Mudcat experts?