A Memrise new-comer here, after 3 weeks with the app I can say it’s probably my favourite app for learning Spanish and I tried a few. I absolutely love the “real-world-like” experience of Memrise vs just cramming as many disconnected words as possible, with sometimes computer-generated voices. Hearing same phrase by multiple speakers is a genius feature, as is the fact that from “get go” there are real world usages of words/phrases shown.
Now to point: I love the little videos for “comprehension test” AKA “Whizz Quiz” but I really wish I could replay the old ones after the initial session. I understand if perhaps you don’t want to “unlock” all of them to keep as motivating factor, but the ones for older lessons I think should be available somehow, to allow listening to them again.