I also have been having the same problem with multiple of my world's it show's it's loading but it never moved! I just bought a new world a few day's ago and I haven't gotten to play it since, I uploaded Minecraft today and I was about to play it but I saw it had to download yet when I bought It, it said It was successfully downloaded. How do I fix it??
Oh I just went into the world and it isn't doing it anymore the rain is fixed and the textures of the blocks are fixed as well! I think I just needed to close and re-open Minecraft 😃