Got HTTP status 404 Not Found for "http://roaringjelly.org/~jc/music/book/Book42/Nelson.abc"
pngcmd="(./ps2png 512 512 /Users/jc/w/tmp/Tune-5490-Nelson.ps) >>/Users/jc/w/tmp/Tune-5490-get.log 2>&1" returned status 256
http://roaringjelly.org/~jc/music/book/Book42/Nelson.abc

Error exit status 256; here are some files to check:
[P=tuneget V=1/1 B=0 scale=0.70 512x512 PNG]
filesizedescription
Tune-5490-Nelson.abc 145 ABC music file with the extracted tune(s)
Tune-5490-Nelson.ps 6 PostScript
Tune-5490-Nelson.txt 145 Plain-text file with the extracted tune(s)
Tune-5490-get.log 3992 Log file, useful mostly for debugging
Tune-54903-get.log 5854 Log file, useful mostly for debugging
Tune-54905-get.log 8667 Log file, useful mostly for debugging
Tune-54906-get.log 4133 Log file, useful mostly for debugging
Tune-54909-DanielWright_CCCCD.abc 157 ABC music file with the extracted tune(s)
Tune-54909-DanielWright_CCCCD.pdf 2217 Portable Data Format
Tune-54909-DanielWright_CCCCD.ps 6 PostScript
Tune-54909-DanielWright_CCCCD.txt 157 Plain-text file with the extracted tune(s)
Tune-54909-get.log 5126 Log file, useful mostly for debugging
These files should be available for 24 hours.