Got HTTP status 404 Not Found for "http://john-chambers.us/~jc/music/book/MusiciansCompanionP1/dim.abc"
pngcmd="(./ps2png 512 512 /Users/jc/w/tmp/Tune-4853-dim.ps) >>/Users/jc/w/tmp/Tune-4853-get.log 2>&1" returned status 256
http://john-chambers.us/~jc/music/book/MusiciansCompanionP1/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
Coll_48533.log 458412 Log file, useful mostly for debugging
Tune-4853-dim.abc 156 ABC music file with the extracted tune(s)
Tune-4853-dim.ps 6 PostScript
Tune-4853-dim.txt 156 Plain-text file with the extracted tune(s)
Tune-4853-get.log 4015 Log file, useful mostly for debugging
Tune-48531-get.log 4819 Log file, useful mostly for debugging
Tune-48534-WilliamCampbell_10thBook_1798-V2.abc 172 ABC music file with the extracted tune(s)
Tune-48534-WilliamCampbell_10thBook_1798-V2.txt 172 Plain-text file with the extracted tune(s)
Tune-48534-get.log 3598 Log file, useful mostly for debugging
Tune-48535-get.log 4332 Log file, useful mostly for debugging
Tune-48537-get.log 10857 Log file, useful mostly for debugging
Tune-48539-get.log 8057 Log file, useful mostly for debugging
These files should be available for 24 hours.