Got HTTP status 404 Not Found for "http://roaringjelly.org/~jc/music/book/AmericanSD/_.abc"
pngcmd="(./ps2png 512 512 /Users/jc/w/tmp/Tune-50634-_.ps) >>/Users/jc/w/tmp/Tune-50634-get.log 2>&1" returned status 256
http://roaringjelly.org/~jc/music/book/AmericanSD/_.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-50634-Ann_Sheehy_McAuliffe.abc 403 ABC music file with the extracted tune(s)
Tune-50634-Ann_Sheehy_McAuliffe.gif 0 Graphics Interchange Format, the proprietary scan-line picture format
Tune-50634-Ann_Sheehy_McAuliffe.ps 34344 PostScript
Tune-50634-Ann_Sheehy_McAuliffe.txt 403 Plain-text file with the extracted tune(s)
Tune-50634-_.abc 144 ABC music file with the extracted tune(s)
Tune-50634-_.ps 6 PostScript
Tune-50634-_.txt 144 Plain-text file with the extracted tune(s)
Tune-50634-get.log 15529 Log file, useful mostly for debugging
These files should be available for 24 hours.