pngcmd="(./ps2png 512 512 /Users/jc/w/tmp/Tune-4344-1560_mh.ps) >>/Users/jc/w/tmp/Tune-4344-get.log 2>&1" returned status 256
http://john-chambers.us/~jc/music/book/oneills/1850/X/1560_mh.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_43440.log 140992 Log file, useful mostly for debugging
Form_43444.log 783 Log file, useful mostly for debugging
Tune-4344-1560_mh.abc 537 ABC music file with the extracted tune(s)
Tune-4344-1560_mh.ps 40337 PostScript
Tune-4344-1560_mh.txt 537 Plain-text file with the extracted tune(s)
Tune-4344-get.log 4177 Log file, useful mostly for debugging
Tune-43440-get.log 3010 Log file, useful mostly for debugging
Tune-43441-get.log 6198 Log file, useful mostly for debugging
These files should be available for 24 hours.