pngcmd="(./ps2png 512 512 /Users/jc/w/tmp/Tune-17991-8189_Tommys_Chance.ps) >>/Users/jc/w/tmp/Tune-17991-get.log 2>&1" returned status 256
http://roaringjelly.org/~jc/music/book/JohnJohnson/8189_Tommys_Chance.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_17991.log 266066 Log file, useful mostly for debugging
Form_17991.log 2467 Log file, useful mostly for debugging
Tune-17991-8189_Tommys_Chance.abc 375 ABC music file with the extracted tune(s)
Tune-17991-8189_Tommys_Chance.ps 33767 PostScript
Tune-17991-8189_Tommys_Chance.txt 375 Plain-text file with the extracted tune(s)
Tune-17991-get.log 4690 Log file, useful mostly for debugging
These files should be available for 24 hours.