X:0 not found in http://john-chambers.us/~jc/music/book/BostonCollection/1450_.abc
pngcmd="(./ps2png 512 512 /Users/jc/w/tmp/Tune-14256-1450_.ps) >>/Users/jc/w/tmp/Tune-14256-get.log 2>&1" returned status 256
http://john-chambers.us/~jc/music/book/BostonCollection/1450_.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-14256-1450_.abc 0 ABC music file with the extracted tune(s)
Tune-14256-1450_.ps 6 PostScript
Tune-14256-1450_.txt 0 Plain-text file with the extracted tune(s)
Tune-14256-get.log 3984 Log file, useful mostly for debugging
These files should be available for 24 hours.