Got HTTP status 404 Not Found for "http://john-chambers.us/~jc/music/book/1798/CDSS_Gems.abc"
pngcmd="(./ps2png 512 512 /Users/jc/w/tmp/Tune-5884-CDSS_Gems.ps) >>/Users/jc/w/tmp/Tune-5884-get.log 2>&1" returned status 256
http://john-chambers.us/~jc/music/book/1798/CDSS_Gems.abc

Error exit status 256; here are some files to check:
[P=tuneget V=1/1 B=0 scale=0.70 512x512 PNG]
filesizedescription
Find_58849.log 1479 Log file, useful mostly for debugging
Tune-5884-CDSS_Gems.abc 146 ABC music file with the extracted tune(s)
Tune-5884-CDSS_Gems.ps 6 PostScript
Tune-5884-CDSS_Gems.txt 146 Plain-text file with the extracted tune(s)
Tune-5884-get.log 4047 Log file, useful mostly for debugging
Tune-58847-get.log 260687 Log file, useful mostly for debugging
Tune-58849-Kerr_MM3-V2.abc 146 ABC music file with the extracted tune(s)
Tune-58849-Kerr_MM3-V2.pdf 2217 Portable Data Format
Tune-58849-Kerr_MM3-V2.ps 6 PostScript
Tune-58849-Kerr_MM3-V2.txt 146 Plain-text file with the extracted tune(s)
Tune-58849-get.log 4899 Log file, useful mostly for debugging
These files should be available for 24 hours.