Adding shortcode to external splash page

Hi,

I want to display a splash page before my theme loads, I have figured out how to do that and I will post my code below, but what I also need to do is use shortcode on the splash page as well. I have come close to getting it, but not the cigar ??

<?php

/**
 * Front to the WordPress application. This file doesn't do anything, but loads
 * wp-blog-header.php which does and tells WordPress to load the theme.
 *
 * @package WordPress
 */

/**
 * Tells WordPress to load the WordPress theme and output it.
 *
 * @var bool
 */
define('WP_USE_THEMES', false);

/** Loads the WordPress Environment and Template */
require( dirname( __FILE__ ) . '/wp-blog-header.php' );
require( 'wp-load.php' );

get_header();

echo do_shortcode('[wpgmza id="1"]');

get_footer();

?>

So far, what I have found is that I need to have the get_header(); and get_footer(); code in place to get the shortcode working, but by using the header and footer, I am getting the whole look of the theme as well, I just want the background / blank page. Is there some way to do this?

NOTE: I don’t know if this is going to make a difference, most likely will, the code above is from the wordpress installation path, currently: /var/www/html/wordpress/index.php

I am going to use /var/www/html/index.php using .htaccess DirectoryIndex to specifiy my splash.php page like so:

.htaccess file:

# BEGIN WordPress

<IfModule mod_rewrite.c>
RewriteEngine On
RewriteBase /
RewriteRule ^index\.php$ - [L]
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule . /index.php [L]
</IfModule>

# END WordPress

DirectoryIndex index.html splash.php

Thank you
Brian