Got HTTP status 404 Not Found for "http://john-chambers.us/~jc/music/book/1758/RSCDS_Graded1.abc"
pngcmd="(./ps2png 512 512 /Users/jc/w/tmp/Tune-4916-RSCDS_Graded1.ps) >>/Users/jc/w/tmp/Tune-4916-get.log 2>&1" returned status 256
http://john-chambers.us/~jc/music/book/1758/RSCDS_Graded1.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-4916-RSCDS_Graded1.abc 150 ABC music file with the extracted tune(s)
Tune-4916-RSCDS_Graded1.ps 6 PostScript
Tune-4916-RSCDS_Graded1.txt 150 Plain-text file with the extracted tune(s)
Tune-4916-get.log 4125 Log file, useful mostly for debugging
Tune-49160-Gow-CR-abc1.abc 148 ABC music file with the extracted tune(s)
Tune-49160-Gow-CR-abc1.ps 6 PostScript
Tune-49160-Gow-CR-abc1.txt 148 Plain-text file with the extracted tune(s)
Tune-49160-get.log 4010 Log file, useful mostly for debugging
Tune-49162-Gow-CR-abc1.abc 148 ABC music file with the extracted tune(s)
Tune-49162-Gow-CR-abc1.ps 6 PostScript
Tune-49162-Gow-CR-abc1.txt 148 Plain-text file with the extracted tune(s)
Tune-49162-get.log 4010 Log file, useful mostly for debugging
Tune-49165-get.log 5869 Log file, useful mostly for debugging
Tune-49168-Pioneer.abc 144 ABC music file with the extracted tune(s)
Tune-49168-Pioneer.pdf 2209 Portable Data Format
Tune-49168-Pioneer.ps 6 PostScript
Tune-49168-Pioneer.txt 144 Plain-text file with the extracted tune(s)
Tune-49168-get.log 4793 Log file, useful mostly for debugging
These files should be available for 24 hours.