If you create a new subtemplate, the '.php' extension is missing. In addition if you try to copy an existing subtemplate, the new template is created but nothing is copied. This patch will fix this issue.
edit the file 'montezuma/admin/options/650_sub_templates.php and change line 218 from
to
HTML Code:
<select id="make_copy_of">
and change line 411 from
HTML Code:
'title' => $title,
to
HTML Code:
'title' => $title . '<span style="color:#666">.php</span>',
or replace the file montezuma/admin/options/650_sub_templates.php with the attached file which has the correction already applied.