There's a Javascript message in the Error Console on that page which says:
Uncaught Error: You must specify a valid JavaScript API Domain as part of this key's configuration.
It sounds like you didn't create your LinkedIn application correctly. Please make sure you filled in the Javascript API setting as noted in the
Joomla / LinkedIn configuration guide
.
Hope that helps, but if not, let us know. Finally, I'll be moving this thread to the JLinked / Joomla 2.5 area after this post instead of the JFBConnect area. Look for it there later on.
Thanks,
Alex