Cloud programs do not use serial numbers... you log in to your paid Cloud account to download & install & activate... you MAY need to log out of the Cloud and restart your computer and log back in to the Cloud for things to work
Some general information
http://www.adobe.com/products/creativecloud/faq.html
http://helpx.adobe.com/creative-cloud/help/install-apps.html to install or uninstall
http://forums.adobe.com/community/download_install_setup/creative_cloud_faq
What it is http://helpx.adobe.com/creative-cloud/help/creative-cloud-desktop.html
Cloud Getting Started https://helpx.adobe.com/creative-cloud.html
A chat session where an agent may remotely look in your computer may help
NEW Chat link (from a Moderator message dated 7-19-14)
Creative Cloud support (all Creative Cloud customer service issues)
