Currently all mod-rewrite urls are ended with ".html". This is not quite customizable. I propose to create a configuration variable e.g. RewriteUrlEnding of dropdown type with such values: "" (empty), "/", ".html". To be more custom user could specify url ending for each url individually using "url_ending" parameter of "m_Link" tag (e.g. <inp2:m_Link template="path/to/template" url_ending="/"/>).
During parsing all possible rewrite url ending will be stripped from the end of url before passing it to registered rewrite listeners. In case if developer have specified it's own url ending (via "url_ending" parameter), then of course it won't be stripped properly.