pngcmd="(./ps2png 512 512 /Users/jc/w/tmp/Tune-74715-09Duet.ps) >>/Users/jc/w/tmp/Tune-74715-get.log 2>&1" returned status 256
http://www.campin.me.uk/Flute/Webrelease/Flute/09Duet/09Duet.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
Tune-74715-09Duet.abc 487 ABC music file with the extracted tune(s)
Tune-74715-09Duet.ps 36254 PostScript
Tune-74715-09Duet.txt 487 Plain-text file with the extracted tune(s)
Tune-74715-get.log 8927 Log file, useful mostly for debugging
These files should be available for 24 hours.