[HELP]- Adding code to Index causes problems

When as instructed I add this to my index (vbadvanced)

PHP Code:

// ibProArcade
if($_POST['module'] == "pnFlashGames")
{
    require_once('./global.php');

    switch($_POST['func'])
    {
        case "storeScore":
        $_GET['act'] = "Arcade";
        $_GET['module'] = "arcade";
        $_GET['do'] = "pnFStoreScore";
        break;

        case "saveGame":
        $_GET['do'] = "pnFSaveGame";
        break;

        case "loadGame":
        $_GET['do'] = "pnFLoadGame";
        break;

        case "loadGameScores":
        $gid = $vbulletin->input->clean_gpc('p', 'gid', TYPE_INT);
        $uid= $vbulletin->userinfo['userid'];
        $game = $db->query_first("SELECT * FROM " . TABLE_PREFIX . "games_scores WHERE mid=$uid AND gid = $gid ORDER BY score DESC LIMIT 0,1");
        $scores = $game[score];

        if($scores != false)
        {
            //Return true
            print "&opSuccess=true&gameScores=$scores&endvar=1"; //send endvar to keep opSuccess separate from all other output from PostNuke
        }
        else
        {
            print "&opSuccess=false&error=Error&endvar=1";
        }
        break;
    }
}

$act = $_GET[act];
$autocom = $_GET[autocom];
$showuser= $_GET[showuser];
if($act == "Arcade" || $autocom=="arcade") {
include "arcade.php";
exit();
}
if(!empty($showuser) && $showuser >= 1) {
$u = $showuser;
$_GET[u] = $showuser;
include "member.php";
exit();
}

// end of ibProArcade 


I get these error messages at the top of my forum page. Can anyone help. An arcade that does not record score is not popular

Notice: Undefined index: module in D:\home\Default\mysite.co.uk\htdocs\index.php on line 3

Notice: Use of undefined constant act - assumed 'act' in D:\home\Default\mysite.co.uk\htdocs\index.php on line 42

Notice: Undefined index: act in D:\home\Default\mysite.co.uk\htdocs\index.php on line 42

Notice: Use of undefined constant autocom - assumed 'autocom' in D:\home\Default\mysite.co.uk\htdocs\index.php on line 43

Notice: Undefined index: autocom in D:\home\Default\mysite.co.uk\htdocs\index.php on line 43

Notice: Use of undefined constant showuser - assumed 'showuser' in D:\home\Default\mysite.co.uk\htdocs\index.php on line 44

Notice: Undefined index: showuser in D:\home\Default\mysite.co.uk\htdocs\index.php on line 44

[jimjam]

Still cannot the arcade to save scores, have tried loads, but when I add the code to my index I still get the errors outlined above, can anyone help me out here? Thanks