pngcmd="(./ps2png 512 512 /Users/jc/w/tmp/Tune-54890-BlackJoke.ps) >>/Users/jc/w/tmp/Tune-54890-get.log 2>&1" returned status 256
http://john-chambers.us/~jc/England/BlackJoke.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-54890-BlackJoke.abc 1884 ABC music file with the extracted tune(s)
Tune-54890-BlackJoke.ps 45315 PostScript
Tune-54890-BlackJoke.txt 1884 Plain-text file with the extracted tune(s)
Tune-54890-get.log 4780 Log file, useful mostly for debugging
These files should be available for 24 hours.