Problem:    Modelines in source code are inconsistant.
Solution:   Use the same line in most files.  Add 'noet'.  (Naruhiko Nishino)

Problem:    Background color response with transparency is not ignored.
Solution:   Change the way escape sequences are recognized. (partly by
            Hirohito Higashi)

Problem:    For EBCDIC pound sign is defined as 't'.
Solution:   Correctly define POUND.

Problem:    MSVC compiler has a problem with non-ASCII characters.
Solution:   Avoid non-ASCII characters. (Hong Xu)

Problem:    The RISC OS port has obvious errors and is not being maintained.
Solution:   Remove the RISC OS files and code.