Got HTTP status 404 Not Found for "http://john-chambers.us/~jc/music/book/Scotia/CMCIT.abc"
pngcmd="(./ps2png 512 512 /Users/jc/w/tmp/Tune-3854-CMCIT.ps) >>/Users/jc/w/tmp/Tune-3854-get.log 2>&1" returned status 256
http://john-chambers.us/~jc/music/book/Scotia/CMCIT.abc

Error exit status 256; here are some files to check:
[P=tuneget V=1/1 B=0 scale=0.70 512x512 PNG]
filesizedescription
Tune-3854-CMCIT.abc 144 ABC music file with the extracted tune(s)
Tune-3854-CMCIT.ps 6 PostScript
Tune-3854-CMCIT.txt 144 Plain-text file with the extracted tune(s)
Tune-3854-get.log 3973 Log file, useful mostly for debugging
Tune-38540-get.log 4367 Log file, useful mostly for debugging
Tune-38541-get.log 3434 Log file, useful mostly for debugging
Tune-38543-get.log 8063 Log file, useful mostly for debugging
Tune-38544-get.log 4003 Log file, useful mostly for debugging
Tune-38546-get.log 9117 Log file, useful mostly for debugging
Tune-38549-get.log 3867 Log file, useful mostly for debugging
These files should be available for 24 hours.