I enter a Release Date correctly to my movies but then it does not appear as you can check for the images.
Sometimes it shows the date but always when I add another movie to the folder of my movies, the release date of the previous movies disappears.
this could be because you’re using a movie library for home videos… when you show those films by release date, the actual date should be visible.
I recommend to change the library type to Personal Media instead… this way Plex will by default use any embedded metadata it can read/find but you’ll still be able to enrich the data / posters etc.
Plus… Plex won’t attempt to match your movies against an online database.
If I remember correctly, this should also resolve your 2nd problem:
