pngcmd="(./ps2png 512 512 /Users/jc/w/tmp/Tune-75084-001_Chevy_Chase.ps) >>/Users/jc/w/tmp/Tune-75084-get.log 2>&1" returned status 256
http://john-chambers.us/~jc/music/book/NorthumbrianMinstrelsy/001_Chevy_Chase.abc

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-75084-001_Chevy_Chase.abc 169 ABC music file with the extracted tune(s)
Tune-75084-001_Chevy_Chase.ps 32318 PostScript
Tune-75084-001_Chevy_Chase.txt 169 Plain-text file with the extracted tune(s)
Tune-75084-get.log 4351 Log file, useful mostly for debugging
These files should be available for 24 hours.