BLANK Cloud Screen http://forums.adobe.com/message/5484303 may help
-and step by step http://forums.adobe.com/thread/1440508?tstart=0
-and http://helpx.adobe.com/creative-cloud/kb/blank-white-screen-ccp.html
or
Chat Now button near the bottom for Activation and Deactivation problems may help
http://helpx.adobe.com/x-productkb/policy-pricing/activation-deactivation-products.html
or
http://helpx.adobe.com/creative-cloud/kb/license-this-software.html
Membership and Payments http://helpx.adobe.com/x-productkb/policy-pricing/membership-subscription-troubleshooting- creative-cloud.html