pngcmd="(./ps2png 512 512 /Users/jc/w/tmp/Tune-65678-Rev20180509.ps) >>/Users/jc/w/tmp/Tune-65678-get.log 2>&1" returned status 256
http://john-chambers.us/~jc/music/abc/Finland/Rev20180509.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-65678-Rev20180509.abc 3750 ABC music file with the extracted tune(s)
Tune-65678-Rev20180509.ps 64159 PostScript
Tune-65678-Rev20180509.txt 3750 Plain-text file with the extracted tune(s)
Tune-65678-get.log 11098 Log file, useful mostly for debugging
These files should be available for 24 hours.