I’m afraid the latest update broke something in regards to the way posters are loaded. But as far as I can see this is only happening with stuff that is synced via Trakt, for example “history”, “watchlist”, “rated movies/shows” and so on. The problem is that randomly a lot of posters for movies shows won’t load when in the main screen. See for example the first Screenshot. You can however force to load the poster when you go into the detail view of the movie/show. Afterwards it will show (see second screenshot).
Have a great day!