pngcmd="(./ps2png 512 512 /Users/jc/w/tmp/Tune-23123-kbdproto.ps) >>/Users/jc/w/tmp/Tune-23123-get.log 2>&1" returned status 256
http://john-chambers.us/~jc/music/book/EverydaySongBook/kbdproto.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-23123-get.log 4600 Log file, useful mostly for debugging
Tune-23123-kbdproto.abc 483 ABC music file with the extracted tune(s)
Tune-23123-kbdproto.ps 30967 PostScript
Tune-23123-kbdproto.txt 483 Plain-text file with the extracted tune(s)
These files should be available for 24 hours.