First up what a great idea to have an abc notation forum. Been using it for years - in the dark.
I'm using abcm2ps on OSX. I recently went to the sourceforge download page to get the lastest binary - http://abcplus.sourceforge.net/
But the file offered for OSX - abcm2ps-5.9.13-osx.zip - when unzipped appears to be unrecognisable to my system. Can't open it, execute it. Is there anyone else here on mac that has recently installed the latest version?