If I'm looking at the correct title page, the main page does have a release year listed. Also, only one of the 10 episode pages lists a release date. Go to the first episode page (#1.1) and add the missing release date in the Release Dates section. The date displayed for a show's title page is usually from the first listed episode.
After the update has been processed, then you'll be able to post a rating for the title page.