pngcmd="(./ps2png 512 512 /Users/jc/w/tmp/Tune-11450-session2.ps) >>/Users/jc/w/tmp/Tune-11450-get.log 2>&1" returned status 256
http://wellington.session.nz/tunebooks/other/session2.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-11450-get.log 4597 Log file, useful mostly for debugging
Tune-11450-session2.abc 246 ABC music file with the extracted tune(s)
Tune-11450-session2.ps 34749 PostScript
Tune-11450-session2.txt 246 Plain-text file with the extracted tune(s)
These files should be available for 24 hours.