pngcmd="(./ps2png 512 512 /Users/jc/w/tmp/Tune-55178-1772_Rutherford_12SelectedCountryDances.ps) >>/Users/jc/w/tmp/Tune-55178-get.log 2>&1" returned status 256
http://john-chambers.us/~jc/music/book/DftY/1772_Rutherford_12SelectedCountryDances.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-55178-1772_Rutherford_12SelectedCountryDances.abc 10118 ABC music file with the extracted tune(s)
Tune-55178-1772_Rutherford_12SelectedCountryDances.ps 124733 PostScript
Tune-55178-1772_Rutherford_12SelectedCountryDances.txt 10118 Plain-text file with the extracted tune(s)
Tune-55178-get.log 13121 Log file, useful mostly for debugging
These files should be available for 24 hours.