pscmd="(jcabc2ps /Users/jc/w/tmp/Tune-6082-CR3-abc2.abc -F fmt/pdf_55.fmt +s 0.55 +maxs 2000 )>/Users/jc/w/tmp/Tune-6082-CR3-abc2.ps 2>>/Users/jc/w/tmp/Tune-6082-get.log" returned status 35584.
pngcmd="(./ps2png 512 512 /Users/jc/w/tmp/Tune-6082-CR3-abc2.ps) >>/Users/jc/w/tmp/Tune-6082-get.log 2>&1" returned status 256
http://john-chambers.us/~jc/music/book/Gow/CR3-abc2.abc

Error exit status 256; here are some files to check:
[get.cgi V=1/1 B=0 scale=0.55 512x512 PNG]
filesizedescription
Tune-6082-CR3-abc2.abc 94746 ABC music file with the extracted tune(s)
Tune-6082-CR3-abc2.ps 137029 PostScript
Tune-6082-CR3-abc2.txt 94746 Plain-text file with the extracted tune(s)
Tune-6082-get.log 65317 Log file, useful mostly for debugging
Tune-60828-193_SpeedThePlough.abc 895 ABC music file with the extracted tune(s)
Tune-60828-193_SpeedThePlough.gif 0 Graphics Interchange Format, the proprietary scan-line picture format
Tune-60828-193_SpeedThePlough.ps 40306 PostScript
Tune-60828-193_SpeedThePlough.txt 895 Plain-text file with the extracted tune(s)
Tune-60828-get.log 5467 Log file, useful mostly for debugging
These files should be available for 24 hours.