Hi, I found the post that worked for me before:
(Thanks to @sarajty)
I had the same issue with the index.html file repeating the Flash intro over and over again. I ended up re-naming the page intro.html and it solved the repeat issue.
Then in order for the intro.html page to load at the main URL, and load only once, I changed the index.php file to this:
$_SESSION['flashIntroShown'] = 1;
I didn't have to make any changes to the rest of the wordpress site. Hope that helps!
The original post was here.