Got HTTP status 404 Not Found for "http://john-chambers.us/~jc/music/book/mixed/Glen2.abc"
pngcmd="(./ps2png 512 512 /Users/jc/w/tmp/Tune-3579-Glen2.ps) >>/Users/jc/w/tmp/Tune-3579-get.log 2>&1" returned status 256
http://john-chambers.us/~jc/music/book/mixed/Glen2.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_3579.log 269411 Log file, useful mostly for debugging
Coll_35792.log 327771 Log file, useful mostly for debugging
Coll_35798.log 294609 Log file, useful mostly for debugging
Coll_35799.log 932220 Log file, useful mostly for debugging
Tune-3579-Glen2.abc 143 ABC music file with the extracted tune(s)
Tune-3579-Glen2.ps 6 PostScript
Tune-3579-Glen2.txt 143 Plain-text file with the extracted tune(s)
Tune-3579-get.log 3965 Log file, useful mostly for debugging
Tune-35792-get.log 4543 Log file, useful mostly for debugging
Tune-35793-get.log 4275 Log file, useful mostly for debugging
These files should be available for 24 hours.