pngcmd="(./ps2png 512 512 /Users/jc/w/tmp/Tune-67201-059_Christmas_Song.ps) >>/Users/jc/w/tmp/Tune-67201-get.log 2>&1" returned status 256
http://john-chambers.us/~jc/music/book/EverydaySongBook/059_Christmas_Song.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-67201-059_Christmas_Song.abc 914 ABC music file with the extracted tune(s)
Tune-67201-059_Christmas_Song.ps 34380 PostScript
Tune-67201-059_Christmas_Song.txt 914 Plain-text file with the extracted tune(s)
Tune-67201-get.log 4652 Log file, useful mostly for debugging
These files should be available for 24 hours.