Got HTTP status 404 Not Found for "http://john-chambers.us/~jc/music/book/Book40/MichaelDabney_12Minuets12Dances-1760-V1.abc"
pngcmd="(./ps2png 512 512 /Users/jc/w/tmp/Tune-4215-MichaelDabney_12Minuets12Dances-1760-V1.ps) >>/Users/jc/w/tmp/Tune-4215-get.log 2>&1" returned status 256
http://john-chambers.us/~jc/music/book/Book40/MichaelDabney_12Minuets12Dances-1760-V1.abc

Error exit status 256; here are some files to check:
[P=tuneget V=1/1 B=0 scale=0.70 512x512 PNG]
filesizedescription
Tune-4215-MichaelDabney_12Minuets12Dances-1760-V1.abc 178 ABC music file with the extracted tune(s)
Tune-4215-MichaelDabney_12Minuets12Dances-1760-V1.ps 6 PostScript
Tune-4215-MichaelDabney_12Minuets12Dances-1760-V1.txt 178 Plain-text file with the extracted tune(s)
Tune-4215-get.log 4685 Log file, useful mostly for debugging
Tune-42151-MrKynastonsFamousDance.abc 161 ABC music file with the extracted tune(s)
Tune-42151-MrKynastonsFamousDance.ps 6 PostScript
Tune-42151-MrKynastonsFamousDance.txt 161 Plain-text file with the extracted tune(s)
Tune-42151-get.log 4378 Log file, useful mostly for debugging
Tune-42156-get.log 4916 Log file, useful mostly for debugging
Tune-42159-cresc.abc 144 ABC music file with the extracted tune(s)
Tune-42159-cresc.pdf 2217 Portable Data Format
Tune-42159-cresc.ps 6 PostScript
Tune-42159-cresc.txt 144 Plain-text file with the extracted tune(s)
Tune-42159-get.log 4749 Log file, useful mostly for debugging
These files should be available for 24 hours.