pngcmd="(./ps2png 512 512 /Users/jc/w/tmp/Tune-76597-3153-Johnny_Pringle.ps) >>/Users/jc/w/tmp/Tune-76597-get.log 2>&1" returned status 256
http://john-chambers.us/~jc/music/book/Gow/CR12/3153-Johnny_Pringle.abc1.abc

Error exit status 256; here are some files to check:
[P=tuneget V=1/1 B=0 scale=0.70 512x512 PNG]
filesizedescription
Tune-76597-3153-Johnny_Pringle.abc 947 ABC music file with the extracted tune(s)
Tune-76597-3153-Johnny_Pringle.ps 39873 PostScript
Tune-76597-3153-Johnny_Pringle.txt 947 Plain-text file with the extracted tune(s)
Tune-76597-get.log 4848 Log file, useful mostly for debugging
These files should be available for 24 hours.