pngcmd="(./ps2png 512 512 /Users/jc/w/tmp/Tune-50646-2132_John_Cheap_the_Chapman.ps) >>/Users/jc/w/tmp/Tune-50646-get.log 2>&1" returned status 256
http://john-chambers.us/~jc/music/book/Gow/CR/2132_John_Cheap_the_Chapman.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-50646-2132_John_Cheap_the_Chapman.abc 796 ABC music file with the extracted tune(s)
Tune-50646-2132_John_Cheap_the_Chapman.ps 36936 PostScript
Tune-50646-2132_John_Cheap_the_Chapman.txt 796 Plain-text file with the extracted tune(s)
Tune-50646-get.log 4891 Log file, useful mostly for debugging
These files should be available for 24 hours.