Got HTTP status 404 Not Found for "http://john-chambers.us/~jc/music/book/air/cresc.abc"
pngcmd="(./ps2png 512 512 /Users/jc/w/tmp/Tune-3488-cresc.ps) >>/Users/jc/w/tmp/Tune-3488-get.log 2>&1" returned status 256
http://john-chambers.us/~jc/music/book/air/cresc.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_34881.log 1652919 Log file, useful mostly for debugging
Coll_34885.log 459809 Log file, useful mostly for debugging
Form_34880.log 1013 Log file, useful mostly for debugging
Form_34889.log 982 Log file, useful mostly for debugging
Tune-3488-cresc.abc 141 ABC music file with the extracted tune(s)
Tune-3488-cresc.ps 6 PostScript
Tune-3488-cresc.txt 141 Plain-text file with the extracted tune(s)
Tune-3488-get.log 3953 Log file, useful mostly for debugging
Tune-34880-get.log 3124 Log file, useful mostly for debugging
Tune-34881-get.log 5097 Log file, useful mostly for debugging
Tune-34884-get.log 1294 Log file, useful mostly for debugging
These files should be available for 24 hours.