Got HTTP status 404 Not Found for "http://john-chambers.us/~jc/music/book/_/CSGBT_1794-V2.abc"
pngcmd="(./ps2png 512 512 /Users/jc/w/tmp/Tune-7165-CSGBT_1794-V2.ps) >>/Users/jc/w/tmp/Tune-7165-get.log 2>&1" returned status 256
http://john-chambers.us/~jc/music/book/_/CSGBT_1794-V2.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_7165.log 291355 Log file, useful mostly for debugging
Coll_71650.log 289950 Log file, useful mostly for debugging
Coll_71653.log 281520 Log file, useful mostly for debugging
Coll_71656.log 291355 Log file, useful mostly for debugging
Tune-7165-CSGBT_1794-V2.abc 147 ABC music file with the extracted tune(s)
Tune-7165-CSGBT_1794-V2.ps 6 PostScript
Tune-7165-CSGBT_1794-V2.txt 147 Plain-text file with the extracted tune(s)
Tune-7165-get.log 9028 Log file, useful mostly for debugging
Tune-71650-get.log 7576 Log file, useful mostly for debugging
Tune-71657-get.log 5590 Log file, useful mostly for debugging
These files should be available for 24 hours.