Got HTTP status 404 Not Found for "http://john-chambers.us/~jc/music/book/Book28/Landrin_Potpourri.abc"
pngcmd="(./ps2png 512 512 /Users/jc/w/tmp/Tune-1567-Landrin_Potpourri.ps) >>/Users/jc/w/tmp/Tune-1567-get.log 2>&1" returned status 256
http://john-chambers.us/~jc/music/book/Book28/Landrin_Potpourri.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-1567-Landrin_Potpourri.abc 156 ABC music file with the extracted tune(s)
Tune-1567-Landrin_Potpourri.ps 6 PostScript
Tune-1567-Landrin_Potpourri.txt 156 Plain-text file with the extracted tune(s)
Tune-1567-get.log 11955 Log file, useful mostly for debugging
Tune-15670-get.log 5405 Log file, useful mostly for debugging
Tune-15676-get.log 10385 Log file, useful mostly for debugging
Tune-15678-get.log 5484 Log file, useful mostly for debugging
Tune-15679-get.log 8860 Log file, useful mostly for debugging
These files should be available for 24 hours.