pscmd="(jcabc2ps /Users/jc/w/tmp/Tune-54249-___.abc -F fmt/pdf_60.fmt +s 0.60 +maxs 2000 )>/Users/jc/w/tmp/Tune-54249-___.ps 2>>/Users/jc/w/tmp/Tune-54249-get.log" returned status 256.
http://john-chambers.us/~jc/music/abc/session/waltz/Waltz:Margarets.abc

Error exit status 256; here are some files to check:

[P=get.cgi V=1/1 B=0 scale=0.60 512x512 ]
filesizedescription
Tune-54249-___.abc 0 ABC music file with the extracted tune(s)
Tune-54249-get.log 0 Log file, useful mostly for debugging
These files should be available for 24 hours.