pngcmd="(./ps2png 512 512 /Users/jc/w/tmp/Tune-1541-proto.ps) >>/Users/jc/w/tmp/Tune-1541-get.log 2>&1" returned status 256
http://john-chambers.us/~jc/music/book/proto/proto.abc

Error exit status 256; here are some files to check:
[P=tuneget V=1/1 B=0 scale=0.70 512x512 PNG]
filesizedescription
Form_15412.log 963 Log file, useful mostly for debugging
Tune-1541-get.log 4705 Log file, useful mostly for debugging
Tune-1541-proto.abc 476 ABC music file with the extracted tune(s)
Tune-1541-proto.ps 30668 PostScript
Tune-1541-proto.txt 476 Plain-text file with the extracted tune(s)
Tune-15419-get.log 1370 Log file, useful mostly for debugging
These files should be available for 24 hours.