Problema con include e echo

[trasher666]

io ho questo codice:

/*
+--------------------------------------------------------------------------+
| Include & variabili                                                         |
+--------------------------------------------------------------------------+
*/
    require ("../lang/lang.php");     //File di configurazione
    include ("../config/config.php");      //File di linguaggio

/*
+--------------------------------------------------------------------------+
| Blocco del setup                                                             |
+--------------------------------------------------------------------------+
*/
    if ( file_exists("../install/install.lock") ) //path del file da cercare
        {
    install_error("$lang[50]");                       //se esiste...errore!
    exit();
        }
/*
+--------------------------------------------------------------------------+
|                                                             |
+--------------------------------------------------------------------------+
*/
/*
+--------------------------------------------------------------------------+
| Switch                                                             |
+--------------------------------------------------------------------------+
*/
    function intro()
    {
     echo ("$lang[0]");
    }
    
    function install()
    {
        echo ("<link href=\"install.css\" rel=\"stylesheet\" type=\"text/css\"><center>
         <form name=\"config\" method=\"post\" action=\"index.php?action=check\">
         <table width=\"600\" border=\"0\" cellpadding=1 cellspacing=\"0\" class=\"text\"><tr><td width=144>$lang[7]: </td><td width=144><div align=\"left\">
         <input name=\"SQLprefix\" type=\"text\" class=\"install\"></div></td></tr><tr><td>$lang[2]:      </td>
         <td><div align=\"left\"><input name=\"SQLuser\" type=\"text\" class=\"install\"></div></td></tr>
         <tr><td>$lang[3]: </td><td><div align=\"left\"><input name=\"SQLpass\" type=\"password\" class=\"install\"></div></td></tr><tr>
         <td>$lang[4]: </td><td><div align=\"left\"><input name=\"SQLpass2\" type=\"password\" class=\"install\">
         </div></td></tr><tr><td>$lang[5]: </td><td><div align=\"left\"><input name=\"SQLname\" type=\"text\" class=\"install\"></div></td></tr>
         <tr><td>$lang[6]: </td><td><div align=\"left\"><input name=\"SQLhost\" type=\"text\" class=\"install\">
         </div></td></tr><tr><td>$lang[2]: </td><td><div align=\"left\">
         <input name=\"user\" type=\"text\" class=\"install\">
         </div></td></tr><tr><td>$lang[3]:      </td><td><div align=\"left\">
         <input name=\"pass\" type=\"password\" class=\"install\"></div></td></tr><tr><td>$lang[4]:</td>
         <td><div align=\"left\"><input name=\"pass2\" type=\"password\" class=\"install\"></div></td></tr>
         <tr><td>$lang[24]:</td><td><div align=\"left\"><input name=\"msn\" type=\"text\" class=\"install\"></div>
         </td></tr><tr><td><input type=\"submit\" name=\"Submit\" value=\"$lang[9]\"></td><td></td></tr></table></form></center>");
    }
    
    $action = isset($_GET['action']) ? $_GET['action'] : '';

    switch($action)
    
        {

            default:
                intro();      //Visualizzazione iniziale
            break;
    
            case "install":   //Form setup
                install();
            break;
    
            case "check":     //Controllo informazioni inviate
                check();
            break;
        }
?> 

normalmente dovrebbe prendere le variabili dagli array nella pagina lang.php (../lang/lang.php) se metto l'include e un'echo che rikiama un'array si vede ma in questa pagina non funza si vede solo il form e dove DOVREBBE esserci il testo non compare NULLA