We don't have a way to currently achieve that. The SCLogin module doesn't override the settings of the main component. That may be something we implement in the future, but for now, there's no method for the component's settings to be overridden on a per-page or per-module basis.
If you wanted to create your own logout button, you could *try* the following code:
<a href="#" onclick="jfbc.login.logout_facebook=true;jfbc.login.logout_button_click();">Logout!</a>
I think that will work. In the href, you can put an image or any other text, of course.
Let us know how that goes, and good luck!
Alex