pngcmd="(./ps2png 512 512 /Users/jc/w/tmp/Tune-35643-LargoLawS.ps) >>/Users/jc/w/tmp/Tune-35643-get.log 2>&1" returned status 256
http://john-chambers.us/~jc/music/abc/mirror/terrytraub.org/LargoLawS.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-35643-LargoLawS.abc 465 ABC music file with the extracted tune(s)
Tune-35643-LargoLawS.ps 36453 PostScript
Tune-35643-LargoLawS.txt 465 Plain-text file with the extracted tune(s)
Tune-35643-get.log 4850 Log file, useful mostly for debugging
These files should be available for 24 hours.