JFBconnect login does not work from within Modal Window

Josh,
Unfortunately, this is a known issues. It does work in some modals, but really depends on the implementation. We're working on a way for the 3.2 release (out in next few weeks) which will have the option to use a less Javascripty button which should work with most/all modals.

If you're really antsy or need something sooner, we can try to give you some directions on how to implement it on your own right now. Can't guarantee it will work, but may help you out. Otherwise, hopefully you can wait a little bit for the next release.

Thanks for the compliments on the extension. We definitely work hard on it, and are glad you're happy with it!

Josh,
We do have a fix that was included in the 3.2 release, and I thought I had replied to all discussions of users that were looking for the fix. Obviously, I missed this post, and I apologize for that.

To work in a modal window, you will need to make a minor modification to the JFBCLogin module and replace the current button that's there with a line of code that doesn't require Facebook's Javascript API (like the normal Login With Facebook button). Additionally, this will let you use your own custom image, should you want to, instead of the blue button that's there by default. To read more about it, check out the 2nd and 3rd question in the Common Support Question area:
JFBConnect Common Support Questions

To modify the JFBCLogin module, you should create a template override, which you can read more about below:
Joomla Template Overrides

Should you need any help with this, just let us know, and I can explain further. Hopefully you haven't been waiting on this since March (if you have, let us know), and good luck with your site!
Alex