pngcmd="(./ps2png 512 512 /Users/jc/w/tmp/Tune-67762-SilverGrey.ps) >>/Users/jc/w/tmp/Tune-67762-get.log 2>&1" returned status 256
http://john-chambers.us/~jc/music/abc/Scotland/SilverGrey.txt

Error exit status 256; here are some files to check:
[P=get.cgi V=1/1 B=0 scale=0.60 512x512 PNG]
filesizedescription
Tune-67762-SilverGrey.abc 746 ABC music file with the extracted tune(s)
Tune-67762-SilverGrey.ps 39528 PostScript
Tune-67762-SilverGrey.txt 746 Plain-text file with the extracted tune(s)
Tune-67762-get.log 5337 Log file, useful mostly for debugging
These files should be available for 24 hours.