include virker ikke?

Jeg har flg. include script:

if(isset($_GET["page"])){
    include("house/" . $_GET["page"] .".php");
}else{
    include("house/main.php");
}
Nu prøver jeg r at kalde filen register.php inde fra house mappen vha dette script

Register.php:

<h3>Join</h3>

<?php
//Login part
if($_GET["check"] == "login"){
    if(isset($_POST["login_submit"])) { //Tester om brugeren kommmer fra login form
    $postpw = md5($_POST["pw"]);
    $postemail = customAddslashes($_POST["email"]);
   
    $query = mysql_query("SELECT * FROM users WHERE email = '$postemail' AND pw = '$postpw'") or die(mysql_error()); //Spørger efter ID
   
    $count = mysql_num_rows($query); //Tæller antaller af resultater
        if($count == 1) { //Hvis der kun er et resultat logged in
            while ($row = mysql_fetch_array ($query)) {
                $_SESSION["id"] = $row["id"];
                $_SESSION["email"] = $row["email"];
                $_SESSION["pw"] = $row["pw"];
            }
            $step = "house";
           
        }else{
            $loginstatus = "Wrong e-mail and/or password!";
            $step = "login";
        }
    }
}
if($_GET["step"] == "login"){
    $pageback = "?page=main";
    $pagenext = "house/register.php";
    $check = "login";
    include("login.php");
}

//If new user is selected from step=login, then terms are shown:
if($_GET["check"] == "terms"){
    //validate terms
    echo "Validating terms";
    $step = "newuser";
}
if($_GET["step"] == "terms"){
    $pageback = "?page=register&step=login";
    $pagenext = "house/register.php";
    $check = "terms";
    include("agreement.php");
}

//New user form
if($_GET["check"] == "newuser"){
    //validate newuser
    echo "Validating newuser";
    $step = "house";
}
if($_GET["step"] == "newuser")
    $pageback = "?page=register&step=terms";
    $pagenext = "house/register.php";
    $check = "newuser";
    include("register.php");
}

//Add house form
if($_GET["check"] == "house"){
    //validate house
    echo "Validating house";
    $step = "finish";
}
if($_GET["step"] == "house")
    if($_GET["sender"] == login){   
        $pageback = "?page=register&step=login";
    }elseif($_GET["sender"] == newuser){
        $pageback = "?page=register&step=newuser";
    }
    $pagenext = "house/register.php";
    $check = "house";
    include("house/addhouse.php");
}

if($_GET["step"] == "finish"){
    echo "Thanks for submitting.";
}
?>

Men resultatet er en helt blank side, man kan ikke engang se den øverste overskrift <h3>Join</h3>. Hvordan kan det være?
Jeg har prøvet at include andre side en lige register.php hvor det virkede fint, så problemet ligger altså et eller andet sted i denne fil. Til generel orientering er register_globals sat til off.