Got HTTP status 404 Not Found for "http://john-chambers.us/~jc/music/book/Book18/NorthumbrianMinstrelsy.abc"
pngcmd="(./ps2png 512 512 /Users/jc/w/tmp/Tune-6881-NorthumbrianMinstrelsy.ps) >>/Users/jc/w/tmp/Tune-6881-get.log 2>&1" returned status 256
http://john-chambers.us/~jc/music/book/Book18/NorthumbrianMinstrelsy.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_6881.log 294165 Log file, useful mostly for debugging
Coll_68810.log 567256 Log file, useful mostly for debugging
Coll_68811.log 344409 Log file, useful mostly for debugging
Coll_68814.log 291355 Log file, useful mostly for debugging
Tune-6881-NorthumbrianMinstrelsy.abc 161 ABC music file with the extracted tune(s)
Tune-6881-NorthumbrianMinstrelsy.ps 6 PostScript
Tune-6881-NorthumbrianMinstrelsy.txt 161 Plain-text file with the extracted tune(s)
Tune-6881-get.log 4330 Log file, useful mostly for debugging
Tune-68811-MMM1.abc 154 ABC music file with the extracted tune(s)
Tune-68811-MMM1.txt 154 Plain-text file with the extracted tune(s)
Tune-68811-get.log 5979 Log file, useful mostly for debugging
Tune-68815-get.log 5310 Log file, useful mostly for debugging
Tune-68817-get.log 6052 Log file, useful mostly for debugging
These files should be available for 24 hours.