pngcmd="(./ps2png 512 512 /Users/jc/w/tmp/Tune-5826-TeviotBrig.ps) >>/Users/jc/w/tmp/Tune-5826-get.log 2>&1" returned status 256
http://john-chambers.us/~jc/music/abc/demo/Tunes/TeviotBrig.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_58260.log 136152 Log file, useful mostly for debugging
Form_58261.log 860 Log file, useful mostly for debugging
Form_58268.log 0 Log file, useful mostly for debugging
Tune-5826-TeviotBrig.abc 216 ABC music file with the extracted tune(s)
Tune-5826-TeviotBrig.ps 34870 PostScript
Tune-5826-TeviotBrig.txt 216 Plain-text file with the extracted tune(s)
Tune-5826-get.log 8550 Log file, useful mostly for debugging
Tune-58262-get.log 3806 Log file, useful mostly for debugging
Tune-58264-get.log 3037 Log file, useful mostly for debugging
Tune-58267-get.log 1396 Log file, useful mostly for debugging
Tune-58268-get.log 8210 Log file, useful mostly for debugging
These files should be available for 24 hours.