There's a few easy ways to make the button show up. I'm not sure how their Login box works in that pop-up, but if it's possible to simply use JFBCLogin instead of Joomla's login module (or whatever login module Shape5 distributes), that's easiest.
If not, then you'll need to do a template override of the login module that's showing, and do one of the following:
1) Add the text {JFBCLogin} wherever you want the Login With Facebook button to display
2) Add the custom login button code, described below to add your own image for the Facebook login button. This method is sometimes required in Javascript pop-ups depending on how the pop-up functions:
www.sourcecoast.com/jfbconnect/docs/common-support-questions (Look for the 3rd question "How can I get the Login With Facebook button to work in a Javascript pop-up?"
For more information on template overrides, how to do them, and why, see:
www.sourcecoast.com/extensions/troublesh...s#template-overrides
Hope that helps, but if you need more information, just let us know!