Got HTTP status 404 Not Found for "http://roaringjelly.org/~jc/music/book/ONeills/Rare_Small/0030_Gentle_Ann.abc/book0"
pngcmd="(./ps2png 512 512 /Users/jc/w/tmp/Tune-6863-book0.ps) >>/Users/jc/w/tmp/Tune-6863-get.log 2>&1" returned status 256
http://roaringjelly.org/~jc/music/book/ONeills/Rare_Small/0030_Gentle_Ann.abc/book0

Error exit status 256; here are some files to check:
[get.cgi V=1/1 B=0 scale=0.65 512x512 PNG]
filesizedescription
Sess-68637.log 304966 Log file, useful mostly for debugging
Tune-6863-book0.abc 172 ABC music file with the extracted tune(s)
Tune-6863-book0.ps 6 PostScript
Tune-6863-book0.txt 172 Plain-text file with the extracted tune(s)
Tune-6863-get.log 4097 Log file, useful mostly for debugging
Tune-68630-get.log 8357 Log file, useful mostly for debugging
Tune-68635-get.log 4052 Log file, useful mostly for debugging
Tune-68637-get.log 4151 Log file, useful mostly for debugging
These files should be available for 24 hours.