pngcmd="(./ps2png 512 512 /Users/jc/w/tmp/Tune-3090-20891_Lowell_Sett_tune_4.ps) >>/Users/jc/w/tmp/Tune-3090-get.log 2>&1" returned status 256
http://john-chambers.us/~jc/music/book/EliasHowe/MusiciansCompanionP2/20891_Lowell_Sett_tune_4.abc

Error exit status 256; here are some files to check:
[P=tuneget V=1/1 B=0 scale=0.70 512x512 PNG]
filesizedescription
Coll_30909.log 568660 Log file, useful mostly for debugging
Tune-3090-20891_Lowell_Sett_tune_4.abc 1033 ABC music file with the extracted tune(s)
Tune-3090-20891_Lowell_Sett_tune_4.ps 37133 PostScript
Tune-3090-20891_Lowell_Sett_tune_4.txt 1033 Plain-text file with the extracted tune(s)
Tune-3090-get.log 5025 Log file, useful mostly for debugging
These files should be available for 24 hours.