Got HTTP status 404 Not Found for "http://john-chambers.us/~jc/music/book/Book02/Kerr_MM3-V1.abc"
pngcmd="(./ps2png 512 512 /Users/jc/w/tmp/Tune-6183-Kerr_MM3-V1.ps) >>/Users/jc/w/tmp/Tune-6183-get.log 2>&1" returned status 256
http://john-chambers.us/~jc/music/book/Book02/Kerr_MM3-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-49065-Tune-61830-EFDSS_CDM5.abc 173 ABC music file with the extracted tune(s)
Tune-49065-Tune-61830-EFDSS_CDM5.pdf 2217 Portable Data Format
Tune-49065-Tune-61830-EFDSS_CDM5.ps 6 PostScript
Tune-49065-Tune-61830-EFDSS_CDM5.txt 173 Plain-text file with the extracted tune(s)
Tune-6183-Kerr_MM3-V1.abc 150 ABC music file with the extracted tune(s)
Tune-6183-Kerr_MM3-V1.ps 6 PostScript
Tune-6183-Kerr_MM3-V1.txt 150 Plain-text file with the extracted tune(s)
Tune-6183-get.log 4095 Log file, useful mostly for debugging
Tune-61838-Kerr_MM3-V2.abc 150 ABC music file with the extracted tune(s)
Tune-61838-Kerr_MM3-V2.pdf 2217 Portable Data Format
Tune-61838-Kerr_MM3-V2.ps 6 PostScript
Tune-61838-Kerr_MM3-V2.txt 150 Plain-text file with the extracted tune(s)
Tune-61838-get.log 4925 Log file, useful mostly for debugging
These files should be available for 24 hours.