I have a custom file that opens a browser window which goes to a website that runs a player called 3DVIA. I am using a "Close Window" button as a way to get out of the 3DVIA player. It effectively closes the browser but returns the user to a totally black screen in MediaLab. I know that I am in MediaLab because pressing Crtl-Alt-right arrow takes me to the screen at the end with the message to call the experimenter. Is there any way to resolve the problem of the black screen so that the next item in the MediaLab experiment file will show up properly? I have pasted below the code from the custom item file that contains the "close button" script, if that is of any help.
Thanks!

<html>
<head>
<script src="http://3dlifeplayer.dl.3dvia.com/player/install/DetectBrowser.js"></script>
<script src="http://3dlifeplayer.dl.3dvia.com/player/install/3DLifePlayer_last_version.js"></script>
<script src="http://3dlifeplayer.dl.3dvia.com/player/install/3DLifePlayer.js"></script>
<title>Virtools Generated Page</title>
</head>
<body bgcolor="#000000" text="#00FF00" link="#FFFFFF" vlink="#C0C0C0">
<form method="post">
<input type="button" value="Close Window"
onclick="window.close()">
</form>
<div align="center">
<script language="JavaScript">
Generate3DLifePlayerHtmlTag("prototype2_color.vmo" ,1024,768,"Virtools");
</script>
</div>
</body>
</html>