Got HTTP status 404 Not Found for "http://john-chambers.us/~jc/music/book/abc2/CSRHW-abc2.abc"
pngcmd="(./ps2png 512 512 /Users/jc/w/tmp/Tune-9156-CSRHW-abc2.ps) >>/Users/jc/w/tmp/Tune-9156-get.log 2>&1" returned status 256
http://john-chambers.us/~jc/music/book/abc2/CSRHW-abc2.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-9156-CSRHW-abc2.abc 147 ABC music file with the extracted tune(s)
Tune-9156-CSRHW-abc2.ps 6 PostScript
Tune-9156-CSRHW-abc2.txt 147 Plain-text file with the extracted tune(s)
Tune-9156-get.log 4068 Log file, useful mostly for debugging
Tune-91563-24CountryDances_1771_Thompson.abc 165 ABC music file with the extracted tune(s)
Tune-91563-24CountryDances_1771_Thompson.ps 6 PostScript
Tune-91563-24CountryDances_1771_Thompson.txt 165 Plain-text file with the extracted tune(s)
Tune-91563-24CountryDances_1809_Cahusac_AK.abc 168 ABC music file with the extracted tune(s)
Tune-91563-24CountryDances_1809_Cahusac_AK.txt 168 Plain-text file with the extracted tune(s)
Tune-91563-get.log 8069 Log file, useful mostly for debugging
Tune-91566-get.log 1318 Log file, useful mostly for debugging
Tune-91568-get.log 4241 Log file, useful mostly for debugging
These files should be available for 24 hours.