Got HTTP status 404 Not Found for "http://john-chambers.us/~jc/music/book/1799/Kerr_MM2-V2.abc"
pngcmd="(./ps2png 512 512 /Users/jc/w/tmp/Tune-1379-Kerr_MM2-V2.ps) >>/Users/jc/w/tmp/Tune-1379-get.log 2>&1" returned status 256
http://john-chambers.us/~jc/music/book/1799/Kerr_MM2-V2.abc

Error exit status 256; here are some files to check:
[P=tuneget V=1/1 B=0 scale=0.70 512x512 PNG]
filesizedescription
Coll_13791.log 290409 Log file, useful mostly for debugging
Tune-1379-Kerr_MM2-V2.abc 148 ABC music file with the extracted tune(s)
Tune-1379-Kerr_MM2-V2.ps 6 PostScript
Tune-1379-Kerr_MM2-V2.txt 148 Plain-text file with the extracted tune(s)
Tune-1379-get.log 7317 Log file, useful mostly for debugging
Tune-13792-get.log 3580 Log file, useful mostly for debugging
Tune-13795-ViolaRuth_Pioneer.abc 154 ABC music file with the extracted tune(s)
Tune-13795-ViolaRuth_Pioneer.ps 6 PostScript
Tune-13795-ViolaRuth_Pioneer.txt 154 Plain-text file with the extracted tune(s)
Tune-13795-get.log 4261 Log file, useful mostly for debugging
Tune-13797-get.log 4824 Log file, useful mostly for debugging
These files should be available for 24 hours.