Got HTTP status 404 Not Found for "http://john-chambers.us/~jc/music/book/JamesOswald/CPC/13162_Etrick_Banks.abc/all"
pngcmd="(./ps2png 512 512 /Users/jc/w/tmp/Tune-953-all.ps) >>/Users/jc/w/tmp/Tune-953-get.log 2>&1" returned status 256
http://john-chambers.us/~jc/music/book/JamesOswald/CPC/13162_Etrick_Banks.abc/all

Error exit status 256; here are some files to check:
[get.cgi V=1/1 B=0 scale=0.55 512x512 PNG]
filesizedescription
Coll_95327.log 144738 Log file, useful mostly for debugging
Coll_95344.log 137000 Log file, useful mostly for debugging
Coll_95365.log 129905 Log file, useful mostly for debugging
Coll_95381.log 674921 Log file, useful mostly for debugging
Coll_95397.log 145383 Log file, useful mostly for debugging
Find_95323.log 1518 Log file, useful mostly for debugging
Tune-953-all.abc 170 ABC music file with the extracted tune(s)
Tune-953-all.ps 6 PostScript
Tune-953-all.txt 170 Plain-text file with the extracted tune(s)
Tune-953-get.log 4036 Log file, useful mostly for debugging
Tune-95300-get.log 2198 Log file, useful mostly for debugging
Tune-95339-get.log 1465 Log file, useful mostly for debugging
Tune-95356-get.log 1463 Log file, useful mostly for debugging
Tune-95361-get.log 1506 Log file, useful mostly for debugging
Tune-95392-get.log 1415 Log file, useful mostly for debugging
These files should be available for 24 hours.