Got HTTP status 404 Not Found for "http://roaringjelly.org/~jc/music/book/MacNab01/dance.abc"
pngcmd="(./ps2png 512 512 /Users/jc/w/tmp/Tune-50442-dance.ps) >>/Users/jc/w/tmp/Tune-50442-get.log 2>&1" returned status 256
http://roaringjelly.org/~jc/music/book/MacNab01/dance.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-50442-dance.abc 146 ABC music file with the extracted tune(s)
Tune-50442-dance.ps 6 PostScript
Tune-50442-dance.txt 146 Plain-text file with the extracted tune(s)
Tune-50442-get.log 12592 Log file, useful mostly for debugging
Tune-50442-p6.abc 485 ABC music file with the extracted tune(s)
Tune-50442-p6.gif 0 Graphics Interchange Format, the proprietary scan-line picture format
Tune-50442-p6.ps 30632 PostScript
Tune-50442-p6.txt 485 Plain-text file with the extracted tune(s)
These files should be available for 24 hours.