Are you running php 5 on your server? When you setup the PowerStore did it pass the initial checks? From what I have read you may need to have php5 installed for this to work. You can check on this by creating a php info page then browsing to it on your server.
To make a php info page create a new page and add this line of code to it:
<?php phpinfo(); ?>
This will give you stats on your php server, check to see the version that is listed.