Got HTTP status 404 Not Found for "http://roaringjelly.org/~jc/music/book/Gow4/MMM2.abc"
pngcmd="(./ps2png 512 512 /Users/jc/w/tmp/Tune-3594-MMM2.ps) >>/Users/jc/w/tmp/Tune-3594-get.log 2>&1" returned status 256
http://roaringjelly.org/~jc/music/book/Gow4/MMM2.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-3594-MMM2.abc 141 ABC music file with the extracted tune(s)
Tune-3594-MMM2.ps 6 PostScript
Tune-3594-MMM2.txt 141 Plain-text file with the extracted tune(s)
Tune-3594-get.log 8082 Log file, useful mostly for debugging
Tune-35943-24CountryDances_1805_Thompson.abc 166 ABC music file with the extracted tune(s)
Tune-35943-24CountryDances_1805_Thompson.pdf 2217 Portable Data Format
Tune-35943-24CountryDances_1805_Thompson.ps 6 PostScript
Tune-35943-24CountryDances_1805_Thompson.txt 166 Plain-text file with the extracted tune(s)
Tune-35943-get.log 5433 Log file, useful mostly for debugging
Tune-35948-ArthursSeatWaltzes.abc 155 ABC music file with the extracted tune(s)
Tune-35948-ArthursSeatWaltzes.ps 6 PostScript
Tune-35948-ArthursSeatWaltzes.txt 155 Plain-text file with the extracted tune(s)
Tune-35948-get.log 13060 Log file, useful mostly for debugging
These files should be available for 24 hours.