pngcmd="(./ps2png 512 512 /Users/jc/w/tmp/Tune-4580-Gow4.ps) >>/Users/jc/w/tmp/Tune-4580-get.log 2>&1" returned status 256
http://john-chambers.us/~jc/music/book/Gow/Gow4.abc

Error exit status 256; here are some files to check:
[get.cgi V=1/1 B=0 scale=0.55 512x512 PNG]
filesizedescription
Form_45800.log 845 Log file, useful mostly for debugging
Tune-4580-Gow4.abc 2127 ABC music file with the extracted tune(s)
Tune-4580-Gow4.ps 55719 PostScript
Tune-4580-Gow4.txt 2127 Plain-text file with the extracted tune(s)
Tune-4580-get.log 5433 Log file, useful mostly for debugging
Tune-45807-AmericanSD.abc 8423 ABC music file with the extracted tune(s)
Tune-45807-AmericanSD.gif 0 Graphics Interchange Format, the proprietary scan-line picture format
Tune-45807-AmericanSD.ps 111390 PostScript
Tune-45807-AmericanSD.txt 8423 Plain-text file with the extracted tune(s)
Tune-45807-get.log 12319 Log file, useful mostly for debugging
These files should be available for 24 hours.