Got HTTP status 404 Not Found for "http://john-chambers.us/~jc/music/book/Book22/Kerr_MM4-V1.abc"
pngcmd="(./ps2png 512 512 /Users/jc/w/tmp/Tune-6427-Kerr_MM4-V1.ps) >>/Users/jc/w/tmp/Tune-6427-get.log 2>&1" returned status 256
http://john-chambers.us/~jc/music/book/Book22/Kerr_MM4-V1.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-6427-24CountryDances_1780_Skillern.abc 165 ABC music file with the extracted tune(s)
Tune-6427-24CountryDances_1780_Skillern.ps 6 PostScript
Tune-6427-24CountryDances_1780_Skillern.txt 165 Plain-text file with the extracted tune(s)
Tune-6427-Kerr_MM4-V1.abc 150 ABC music file with the extracted tune(s)
Tune-6427-Kerr_MM4-V1.ps 6 PostScript
Tune-6427-Kerr_MM4-V1.txt 150 Plain-text file with the extracted tune(s)
Tune-6427-get.log 8581 Log file, useful mostly for debugging
Tune-64270-get.log 1328 Log file, useful mostly for debugging
Tune-64274-1812_Wilson_Harmony_FourNewCountryDances.abc 179 ABC music file with the extracted tune(s)
Tune-64274-1812_Wilson_Harmony_FourNewCountryDances.ps 6 PostScript
Tune-64274-1812_Wilson_Harmony_FourNewCountryDances.txt 179 Plain-text file with the extracted tune(s)
Tune-64274-get.log 6078 Log file, useful mostly for debugging
Tune-64279-get.log 1346 Log file, useful mostly for debugging
These files should be available for 24 hours.