At present if you install Wordpress as part of the Web Platform Installer it does not install PHPMyAdmin for you. Luckily this install is very easy to do.
Head over to http://www.phpmyadmin.net and download the latest installer to your server.
Once downloaded unzip the contents of the file and rename the folder to 'phpmyadmin'.
Copy this folder to your website containing Wordpress or php.
Open the file config.sample.inc.php into wordpad (notepad puts it all on one line) and enter in a new Blowfish_secret. It can be anything random like a password.
// $cfg['Servers'][$i]['controluser'] = 'pma';
// $cfg['Servers'][$i]['controlpass'] = 'pmapass';
and replace with the root database username and password or create a new mySQL user called pma and use those details here.
Now uncomment the Storage database and tables - just remove the leading // from each line.
Save and close the config file. Rename it to: 'config.inc.php'.
Copy the phpmyadmin folder and paste it into your website root level.
Go to the Examples folder and open the create_tables.sql file using notepad. Copy all the content in here.
Open your website in a browser and point to yourdomain.com/phpmyadmin
Login using your root database and password. Ignore all the error messages for the moment. Go to SQL and paste in the sql text you copied. Now click on Go.
Log out of phpmyadmin and log in using the database username and password you used when setting up your Wordpress/MySQL database for this project.
Everything should now be working as expected for you.