Got HTTP status 404 Not Found for "http://john-chambers.us/~jc/music/book/JamesOswald/CPC/12332_Come_sweet_Lass.abc/all"
pngcmd="(./ps2png 512 512 /Users/jc/w/tmp/Tune-9643-all.ps) >>/Users/jc/w/tmp/Tune-9643-get.log 2>&1" returned status 256
http://john-chambers.us/~jc/music/book/JamesOswald/CPC/12332_Come_sweet_Lass.abc/all

Error exit status 256; here are some files to check:
[get.cgi V=1/1 B=0 scale=0.55 512x512 PNG]
filesizedescription
Coll_9643.log 466810 Log file, useful mostly for debugging
Coll_96431.log 457009 Log file, useful mostly for debugging
Tune-9643-all.abc 173 ABC music file with the extracted tune(s)
Tune-9643-all.ps 6 PostScript
Tune-9643-all.txt 173 Plain-text file with the extracted tune(s)
Tune-9643-get.log 9503 Log file, useful mostly for debugging
Tune-96437-get.log 1367 Log file, useful mostly for debugging
Tune-96438-get.log 1271 Log file, useful mostly for debugging
Tune-96439-Parks_of_Kilburnie.abc 1057 ABC music file with the extracted tune(s)
Tune-96439-Parks_of_Kilburnie.txt 1057 Plain-text file with the extracted tune(s)
Tune-96439-get.log 3314 Log file, useful mostly for debugging
These files should be available for 24 hours.