I need to download the latest updated version of a plugin
If you have downloaded and installed the Upgrade Me Wordpress Plugin, you should be able to go under "Plugins" in your Wordpress blog and look for the name of the plugin you want to update. If a newer version is available, you will see a yellow box below it with a link that says "Update Automatically." Click that link.
You will always receive an email notification when a major update of a plugin is available. That's why it's important to sign up for updates on the download page (they are free, forever).
If you can't find the latest version, just open a ticket and please include the Paypal email you used to make the purchase with (NOT your Paypal transaction ID) :-)