did you add the classes to your buttons? That won't work. The widget will set the configured class in the top of your DOM node. This enables you to write your own css code to alter the appearance of your app.
so for instance this CSS code:
.app-offline .btn{display:none;}
will hide all your buttons when your app is in offline mode.
Try the new version of the Mobile Features widget. I had a similar problem and that was solved in the new version.