I am trying to play Kingdom Rush as well and the computer says loading and then stops without my saved game information coming up. I presuming now it is a global issue. When will it be fixed is the question.
Please have patience, the staff will be at your service as soon as they can, fixing the issue with the servers and the premium content. If nothing changes by the end of the week, send an email stating your username, the game you are experiencing issues with, the date you purchased paid content and how long it has been unavailable, and they will come back to you as soon as possible to help you through the issues. Until then, please keep calm.