Got HTTP status 404 Not Found for "http://john-chambers.us/~jc/music/book/CNS/Tune-97858-tmp.abc/tmp"
pngcmd="(./ps2png 512 512 /Users/jc/w/tmp/Tune-8828-tmp.ps) >>/Users/jc/w/tmp/Tune-8828-get.log 2>&1" returned status 256
http://john-chambers.us/~jc/music/book/CNS/Tune-97858-tmp.abc/tmp

Error exit status 256; here are some files to check:
[P=get.cgi V=1/1 B=0 scale=0.55 512x512 PNG]
filesizedescription
Coll_8828.log 472928 Log file, useful mostly for debugging
Coll_88280.log 472926 Log file, useful mostly for debugging
Coll_88283.log 274872 Log file, useful mostly for debugging
Coll_88284.log 1793928 Log file, useful mostly for debugging
Coll_88285.log 468771 Log file, useful mostly for debugging
Coll_88287.log 1685059 Log file, useful mostly for debugging
Coll_88289.log 1022826 Log file, useful mostly for debugging
Tune-8828-get.log 8213 Log file, useful mostly for debugging
Tune-8828-tmp.abc 154 ABC music file with the extracted tune(s)
Tune-8828-tmp.ps 6 PostScript
Tune-8828-tmp.txt 154 Plain-text file with the extracted tune(s)
Tune-88282-PostChaise0.abc 171 ABC music file with the extracted tune(s)
Tune-88282-PostChaise0.txt 171 Plain-text file with the extracted tune(s)
Tune-88282-get.log 3382 Log file, useful mostly for debugging
Tune-88283-get.log 3654 Log file, useful mostly for debugging
Tune-88284-get.log 3370 Log file, useful mostly for debugging
Tune-88288-get.log 5269 Log file, useful mostly for debugging
These files should be available for 24 hours.