Got HTTP status 404 Not Found for "http://roaringjelly.org/~jc/music/book/1800/JohnWalsh.abc"
pngcmd="(./ps2png 512 512 /Users/jc/w/tmp/Tune-23047-JohnWalsh.ps) >>/Users/jc/w/tmp/Tune-23047-get.log 2>&1" returned status 256
http://roaringjelly.org/~jc/music/book/1800/JohnWalsh.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-23047-153_Carles_Sally.abc 537 ABC music file with the extracted tune(s)
Tune-23047-153_Carles_Sally.gif 0 Graphics Interchange Format, the proprietary scan-line picture format
Tune-23047-153_Carles_Sally.ps 33339 PostScript
Tune-23047-153_Carles_Sally.txt 537 Plain-text file with the extracted tune(s)
Tune-23047-JohnWalsh.abc 146 ABC music file with the extracted tune(s)
Tune-23047-JohnWalsh.ps 6 PostScript
Tune-23047-JohnWalsh.txt 146 Plain-text file with the extracted tune(s)
Tune-23047-get.log 9485 Log file, useful mostly for debugging
These files should be available for 24 hours.