Oh my what a can of worms. I did some checking and found this list which seems pretty complete for Linux and Windows however I also found left and right parenthesis are allowed in filenames KODI file manager dosen't like them and will cause errors. So possibly KODI's file manager has it's own set of filename rules. Here's the list I found:
The forbidden printable ASCII characters are:
Linux/Unix:
/ (forward slash)
Windows:
< (less than)
> (greater than)
: (colon - sometimes works, but is actually NTFS Alternate Data Streams)
" (double quote)
/ (forward slash)
\ (backslash)
| (vertical bar or pipe)
? (question mark)
* (asterisk)