Got HTTP status 404 Not Found for "http://roaringjelly.org/~jc/music/book/1781/Gow-CR-abc2.abc"
pngcmd="(./ps2png 512 512 /Users/jc/w/tmp/Tune-9325-Gow-CR-abc2.ps) >>/Users/jc/w/tmp/Tune-9325-get.log 2>&1" returned status 256
http://roaringjelly.org/~jc/music/book/1781/Gow-CR-abc2.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-9325-Gow-CR-abc2.abc 148 ABC music file with the extracted tune(s)
Tune-9325-Gow-CR-abc2.ps 6 PostScript
Tune-9325-Gow-CR-abc2.txt 148 Plain-text file with the extracted tune(s)
Tune-9325-get.log 4087 Log file, useful mostly for debugging
Tune-93253-20151_Scotch_March.abc 1456 ABC music file with the extracted tune(s)
Tune-93253-20151_Scotch_March.gif 0 Graphics Interchange Format, the proprietary scan-line picture format
Tune-93253-20151_Scotch_March.ps 45154 PostScript
Tune-93253-20151_Scotch_March.txt 1456 Plain-text file with the extracted tune(s)
Tune-93253-get.log 5674 Log file, useful mostly for debugging
These files should be available for 24 hours.