Got HTTP status 404 Not Found for "http://john-chambers.us/~jc/music/book/1784/Gow-CSR1-abc1.abc"
pngcmd="(./ps2png 512 512 /Users/jc/w/tmp/Tune-6480-Gow-CSR1-abc1.ps) >>/Users/jc/w/tmp/Tune-6480-get.log 2>&1" returned status 256
http://john-chambers.us/~jc/music/book/1784/Gow-CSR1-abc1.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-6480-Gow-CSR1-abc1.abc 150 ABC music file with the extracted tune(s)
Tune-6480-Gow-CSR1-abc1.ps 6 PostScript
Tune-6480-Gow-CSR1-abc1.txt 150 Plain-text file with the extracted tune(s)
Tune-6480-get.log 4125 Log file, useful mostly for debugging
Tune-64800-20152_Burbanks_March.abc 676 ABC music file with the extracted tune(s)
Tune-64800-20152_Burbanks_March.pdf 13841 Portable Data Format
Tune-64800-20152_Burbanks_March.ps 35127 PostScript
Tune-64800-20152_Burbanks_March.txt 676 Plain-text file with the extracted tune(s)
Tune-64800-get.log 6032 Log file, useful mostly for debugging
Tune-64801-get.log 1388 Log file, useful mostly for debugging
Tune-64805-Pat_Shaw_NewWineInOldBottles.abc 165 ABC music file with the extracted tune(s)
Tune-64805-Pat_Shaw_NewWineInOldBottles.txt 165 Plain-text file with the extracted tune(s)
Tune-64805-get.log 3508 Log file, useful mostly for debugging
Tune-64808-get.log 1392 Log file, useful mostly for debugging
These files should be available for 24 hours.