Sorry to hear but thank you very much for the feedback and for trying us out.
The current version listed on WP.org has indeed an "empty" setting page as "settings" were not yet needed. We are aware of the empty page as it is currently there. Sorry for the confusion.
We have extended in the meantime the plug-in, which we are currently testing further internally at this moment. This one will soon be listed on wordpress.org
Please also read this blog post on all feedback we have gathered and improvements we have made on the WordPress plugin:
We will launch to the public anywhere soon with the new version. So stay tuned!
ps. The error you get when logging in to http://sandbox.cleeng.com is something we'll look into immediately.