pngcmd="(./ps2png 512 512 /Users/jc/w/tmp/Tune-67490-Kerr_MM1-V2.ps) >>/Users/jc/w/tmp/Tune-67490-get.log 2>&1" returned status 256
http://john-chambers.us/~jc/music/book/Kerr/MM1/Kerr_MM1-V2.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
Coll_67490.log 145832 Log file, useful mostly for debugging
Sess-67490.log 4232297 Log file, useful mostly for debugging
Tune-67490-Kerr_MM1-V2.abc 460 ABC music file with the extracted tune(s)
Tune-67490-Kerr_MM1-V2.ps 36882 PostScript
Tune-67490-Kerr_MM1-V2.txt 460 Plain-text file with the extracted tune(s)
Tune-67490-get.log 4198 Log file, useful mostly for debugging
These files should be available for 24 hours.