pngcmd="(./ps2png 512 512 /Users/jc/w/tmp/Tune-6850-proto.ps) >>/Users/jc/w/tmp/Tune-6850-get.log 2>&1" returned status 256
http://john-chambers.us/~jc/music/book/WilliamCampbell/10thBook/proto.abc

Error exit status 256; here are some files to check:
[get.cgi V=1/1 B=0 scale=0.55 512x512 PNG]
filesizedescription
Coll_6850.log 291356 Log file, useful mostly for debugging
Coll_68503.log 574280 Log file, useful mostly for debugging
Coll_68504.log 288545 Log file, useful mostly for debugging
Coll_68505.log 280115 Log file, useful mostly for debugging
Coll_68507.log 999140 Log file, useful mostly for debugging
Coll_68508.log 642291 Log file, useful mostly for debugging
Tune-6850-get.log 4747 Log file, useful mostly for debugging
Tune-6850-proto.abc 721 ABC music file with the extracted tune(s)
Tune-6850-proto.ps 30970 PostScript
Tune-6850-proto.txt 721 Plain-text file with the extracted tune(s)
Tune-68500-get.log 3502 Log file, useful mostly for debugging
Tune-68504-get.log 7138 Log file, useful mostly for debugging
Tune-68509-get.log 4537 Log file, useful mostly for debugging
These files should be available for 24 hours.