Think I've figured out the remaining file attribute:
Bit 5 is a flag for marking a file for verification. It can be set by the command
Code:
set "file","r"
which (if my Japanese holds up) says that the file will be verified the next time it is written. Re-saving the file clears the flag, but I think this might be intended for compatibility with tape systems as the VERIFY command only seems to work on cassettes.
Not 100% on this yet. I'd be interested if anyone knows of anything similar on other Sharp machines?