Got HTTP status 404 Not Found for "http://john-chambers.us/~jc/music/book/1826/Kerr_MM2-V1.abc"
pngcmd="(./ps2png 512 512 /Users/jc/w/tmp/Tune-2976-Kerr_MM2-V1.ps) >>/Users/jc/w/tmp/Tune-2976-get.log 2>&1" returned status 256
http://john-chambers.us/~jc/music/book/1826/Kerr_MM2-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-2976-Kerr_MM2-V1.abc 148 ABC music file with the extracted tune(s)
Tune-2976-Kerr_MM2-V1.ps 6 PostScript
Tune-2976-Kerr_MM2-V1.txt 148 Plain-text file with the extracted tune(s)
Tune-2976-get.log 4089 Log file, useful mostly for debugging
Tune-29763-get.log 4808 Log file, useful mostly for debugging
Tune-29764-get.log 1323 Log file, useful mostly for debugging
Tune-29768-CharlesZeuner_TremontQuadrilles1.abc 169 ABC music file with the extracted tune(s)
Tune-29768-CharlesZeuner_TremontQuadrilles1.txt 169 Plain-text file with the extracted tune(s)
Tune-29768-get.log 3584 Log file, useful mostly for debugging
These files should be available for 24 hours.