Where is the button in the composer UI or for the finished post to rate the thread?
I have installed the plugin, given the thread the “rating” tag, and can see the empty stars at the top. But no button to actually rate it. 
(Or must I use a non-admin account for that?)
EDIT: looked closely at the screenshots, and see that there is supposed to be a “Your rating” line there. Well, it’s missing in my instance.
Thought of a second reason this might not work: My instance is German. If the translation is missing…
Will create a test user and set his user interface to English. If it still does not work then something is broken.