Got HTTP status 404 Not Found for "http://john-chambers.us/~jc/music/book/1818/24CountryDances_1810_Button_Whitaker_Elegant.abc"
pngcmd="(./ps2png 512 512 /Users/jc/w/tmp/Tune-8880-24CountryDances_1810_Button_Whitaker_Elegant.ps) >>/Users/jc/w/tmp/Tune-8880-get.log 2>&1" returned status 256
Error exit status 256; here are some files to check: