Hello, if you are not acquainted with Magento, please do not blame us.
If you take a look at the results of our customers feedback, you will see that a 66% of our customers have found the video-tutorial useful and the opinion about the support is that good also (46.2% Good, 12.9% Outstanding). http://www.hellothemes.com/blog/customer-feedback/
We are not saying you HAVE to know Magento, but you could first accept your level of knowledge about this and then make a suggestion, not start spitting over HelloThemes.
Once you have the extension key, you have to paste it in the “Paste extension key to install:” field withing your MagentoConnect Manager in your Admin-panel: System>Magento Connect>Magento Connect Manager
Take a look at which themes are available to install with the extension.