Got HTTP status 404 Not Found for "http://john-chambers.us/~jc/music/book/ScotsMusicalMuseumV5/dim.abc"
pngcmd="(./ps2png 512 512 /Users/jc/w/tmp/Tune-6742-dim.ps) >>/Users/jc/w/tmp/Tune-6742-get.log 2>&1" returned status 256
http://john-chambers.us/~jc/music/book/ScotsMusicalMuseumV5/dim.abc

Error exit status 256; here are some files to check:
[P=tuneget V=1/1 B=0 scale=0.70 512x512 PNG]
filesizedescription
Form_67429.log 876 Log file, useful mostly for debugging
Tune-6742-dim.abc 156 ABC music file with the extracted tune(s)
Tune-6742-dim.ps 6 PostScript
Tune-6742-dim.txt 156 Plain-text file with the extracted tune(s)
Tune-6742-get.log 8363 Log file, useful mostly for debugging
Tune-67420-get.log 8237 Log file, useful mostly for debugging
Tune-67422-get.log 4272 Log file, useful mostly for debugging
Tune-67424-491_Jove_in_his_chair.abc 907 ABC music file with the extracted tune(s)
Tune-67424-491_Jove_in_his_chair.gif 0 Graphics Interchange Format, the proprietary scan-line picture format
Tune-67424-491_Jove_in_his_chair.ps 38873 PostScript
Tune-67424-491_Jove_in_his_chair.txt 907 Plain-text file with the extracted tune(s)
Tune-67424-get.log 5560 Log file, useful mostly for debugging
Tune-67425-get.log 4024 Log file, useful mostly for debugging
Tune-67426-get.log 4513 Log file, useful mostly for debugging
Tune-67429-get.log 4696 Log file, useful mostly for debugging
These files should be available for 24 hours.