There've been some reports on problems with authorisation in our game demo. Some players are currently not able to enter the game. We are terribly sorry for that inconvenience!
We have looked into the problem and found the culprit. We are uploading the solution right now. and we'll inform you as soon as the repairs are complete.
Meanwhile, you can use "guest login" instead of your Desura account to access the game. You can also download a patched client from our server.