Got HTTP status 404 Not Found for "http://john-chambers.us/~jc/music/book/www/GentlemansMagazine.abc"
pngcmd="(./ps2png 512 512 /Users/jc/w/tmp/Tune-2230-GentlemansMagazine.ps) >>/Users/jc/w/tmp/Tune-2230-get.log 2>&1" returned status 256
http://john-chambers.us/~jc/music/book/www/GentlemansMagazine.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-2230-GentlemansMagazine.abc 154 ABC music file with the extracted tune(s)
Tune-2230-GentlemansMagazine.ps 6 PostScript
Tune-2230-GentlemansMagazine.txt 154 Plain-text file with the extracted tune(s)
Tune-2230-get.log 4221 Log file, useful mostly for debugging
Tune-22302-get.log 7084 Log file, useful mostly for debugging
Tune-22303-get.log 4171 Log file, useful mostly for debugging
Tune-22305-get.log 2791 Log file, useful mostly for debugging
Tune-22307-10802_Cotillion_No_7_tune_2-001.svg 22843 Scalable Vector Graphics format
Tune-22307-10802_Cotillion_No_7_tune_2.abc 969 ABC music file with the extracted tune(s)
Tune-22307-10802_Cotillion_No_7_tune_2.txt 969 Plain-text file with the extracted tune(s)
Tune-22307-get.log 10100 Log file, useful mostly for debugging
Tune-22309-get.log 4062 Log file, useful mostly for debugging
These files should be available for 24 hours.