pngcmd="(./ps2png 512 512 /Users/jc/w/tmp/Tune-6830-tunebook.ps) >>/Users/jc/w/tmp/Tune-6830-get.log 2>&1" returned status 256
http://john-chambers.us/~jc/music/abc/mirror/tunebook.org.uk/tunebook.abc

Error exit status 256; here are some files to check:
[P=get.cgi V=1/1 B=0 scale=0.60 512x512 PNG]
filesizedescription
Coll_68303.log 259149 Log file, useful mostly for debugging
Coll_68305.log 139177 Log file, useful mostly for debugging
Tune-6830-get.log 4391 Log file, useful mostly for debugging
Tune-6830-tunebook.abc 664 ABC music file with the extracted tune(s)
Tune-6830-tunebook.ps 34186 PostScript
Tune-6830-tunebook.txt 664 Plain-text file with the extracted tune(s)
Tune-68302-get.log 3867 Log file, useful mostly for debugging
These files should be available for 24 hours.