You were able to add the domain as addon domain because we have temporary allowed adding domains which are not pointed to the server where your account resides. In order for your domain to load properly you would need to point it to the server via A record. You can do that from your CloudFlare account by using the following IP address:
209.58.181.132
If you are not sure how to do that update us with your CloudFlare login details and we will do that for you.
Note that such change might cause a propagation period of up to 24 hours during which your website might not be directly accessible.
Feel free to get back to us if you have any further questions or comments.