Got HTTP status 404 Not Found for "http://roaringjelly.org/~jc/music/book/ONeills/Rare_Small/0077_Roast_Beef.abc/book0"
pngcmd="(./ps2png 512 512 /Users/jc/w/tmp/Tune-4982-book0.ps) >>/Users/jc/w/tmp/Tune-4982-get.log 2>&1" returned status 256
http://roaringjelly.org/~jc/music/book/ONeills/Rare_Small/0077_Roast_Beef.abc/book0

Error exit status 256; here are some files to check:
[get.cgi V=1/1 B=0 scale=0.55 512x512 PNG]
filesizedescription
Coll_49824.log 398851 Log file, useful mostly for debugging
Coll_49826.log 263256 Log file, useful mostly for debugging
Coll_49828.log 780820 Log file, useful mostly for debugging
Form_49822.log 844 Log file, useful mostly for debugging
Tune-4982-book0.abc 172 ABC music file with the extracted tune(s)
Tune-4982-book0.ps 6 PostScript
Tune-4982-book0.txt 172 Plain-text file with the extracted tune(s)
Tune-4982-get.log 4093 Log file, useful mostly for debugging
Tune-49820-get.log 15209 Log file, useful mostly for debugging
Tune-49827-get.log 6836 Log file, useful mostly for debugging
Tune-49829-AMHSI-abc2.abc 158 ABC music file with the extracted tune(s)
Tune-49829-AMHSI-abc2.txt 158 Plain-text file with the extracted tune(s)
Tune-49829-get.log 7059 Log file, useful mostly for debugging
These files should be available for 24 hours.