Installation of plugin went fine, I'll give it one star for that. But after activating version 1.4 of this plugin my blog went offline immediately. So I'm afraid that's all the stars it's going to get from me. Browser window showed some kind of permission error involving incorrect paths to php files in my. Could't even log in. Had to use ftp to get into the plugins folder on the server and delete this facebook plugin to get the site back online again.
So as far as my experience with this plugin goes, it has at least one serious bug: It can cripple your blog.