WordPress Customise

The interstitial page on that website isn’t part of WordPress. It’s just an external page with some ads and a download link on it.

You can easily do this by yourself. Create a php file named download.php on your server and add the following code to it:

<html>
<head>
<meta http-equiv="refresh" content="5; url=<?php $_GET['url'];?>" /></head>
</head>

When you link to this page for the download link to work, do it like this: http://yousite.com/download.php?url=http://thedownloadurl.com/app.exe

You can add whatever else you want to download.php, of course.