pngcmd="(./ps2png 512 512 /Users/jc/w/tmp/Tune-4859-32421_AERIAL_QUADRILLE_4.ps) >>/Users/jc/w/tmp/Tune-4859-get.log 2>&1" returned status 256
http://roaringjelly.org/~jc/music/book/Kohlers/32421_AERIAL_QUADRILLE_4.abc

Error exit status 256; here are some files to check:
[P=tuneget V=1/1 B=0 scale=0.70 512x512 PNG]
filesizedescription
Coll_4859.log 1446919 Log file, useful mostly for debugging
Coll_48590.log 261851 Log file, useful mostly for debugging
Coll_48599.log 263256 Log file, useful mostly for debugging
Form_48593.log 830 Log file, useful mostly for debugging
Form_48594.log 847 Log file, useful mostly for debugging
Form_48595.log 1831 Log file, useful mostly for debugging
Tune-4859-32421_AERIAL_QUADRILLE_4.abc 724 ABC music file with the extracted tune(s)
Tune-4859-32421_AERIAL_QUADRILLE_4.ps 38109 PostScript
Tune-4859-32421_AERIAL_QUADRILLE_4.txt 724 Plain-text file with the extracted tune(s)
Tune-4859-get.log 4242 Log file, useful mostly for debugging
Tune-48596-get.log 4940 Log file, useful mostly for debugging
Tune-48599-get.log 12111 Log file, useful mostly for debugging
These files should be available for 24 hours.