elFinder

You forget to include elFinder:

<script src="elfinder/js/elfinder.min.js" type="text/javascript" charset="utf-8"></script>
<link rel="stylesheet" href="elfinder/css/elfinder.css" type="text/css" media="screen" charset="utf-8" />

Set the correct path for your server.

Yes!

Maybe you should add this to your wiki, I can't see the information here:
http://elrte.org/redmine/projects/elfinder/wiki/Integration_EN#elRTE

Can you help me with TinyMCE and elfinder, probably an easy to find mistake:
elfinder.html

<!-- jQuery and jQuery UI -->
    <script src="elfinder/js/jquery-1.6.1.min.js" type="text/javascript" charset="utf-8"></script>
    <script src="elfinder/js/jquery-ui-1.8.13.custom.min.js" type="text/javascript" charset="utf-8"></script>
    <link rel="stylesheet" href="elfinder/css/smoothness/jquery-ui-1.8.13.custom.css" type="text/css" media="screen" charset="utf-8">
    <script src="elfinder/js/elfinder.min.js" type="text/javascript" charset="utf-8"></script>
<link rel="stylesheet" href="elfinder/css/elfinder.css" type="text/css" media="screen" charset="utf-8" />
<script type="text/javascript">$('#content').elfinder({
     url : 'elfinder/connectors/php/connector.php',
     lang : 'ru',
     editorCallback : function(url) {
       window.tinymceFileWin.document.forms[0].elements[window.tinymceFileField].value = url;
        window.tinymceFileWin.focus();
        window.close();
     }
  })
</script>

The button is displayed, but an empty window is opened.
HTML file with form and tinyMCE

<form method="post" action="">
        <p>     

                <noscript>
                    <input type="submit" value="senden" />
                </noscript>
 <textarea name="content" id="content">
                <?php $incpage = $_GET['page'] . ".inc";
                if ( file_exists( $incpage ) !== false )  
                    include($incpage); 
                else
                    //echo "Fehler: Datei existiert nicht - $incpage";
                ?>
                </textarea>
                <input type="hidden" name="page" value="<?php echo $incpage; ?>" />

        </p>

</form>

tinyMCE config

// content CSS (should be your site CSS)
    content_css : "design.css",
    file_browser_callback : function(field_name, url, type, win) {
        var w = window.open('http://localhost/eis/elfinder.html', null, 'width=600,height=500');
        // Save required parameters in global variables of window (not the best solution, can offer better?)
        // else you can pass parameters using GET and than parse them in elfinder.html
        w.tinymceFileField = field_name;
       w.tinymceFileWin = win;
    }

This howto is not copy-paste it gives the idea how it can work.
Use FireBug to see if you have any errors on the page.
Make sure elfinder.html is valid html you use right container (div/node) for elFinder, in the example about you must have <div id="#content"> in your elfinder.html body. And better wrap elFinder initialization in $().ready(function() { ... });

elFinder initialization REQUIRED to be in $().ready(function() { ... });

Thanks!

These were the problems, brilliant forum!