The lower submissions will appear as you progress into the game. After you finish them, the upper submissions will be unlocked. These are basically H scenes. Despite having indicating numbers, they are free to be unlocked in any order.
H scenes are in the submissions (There will be indicating numbers). You have to beat those missions and another submissions will be unlocked after which you can check them.
Here is a save file that I finished the game choosing to view Mel J ending scene. You can load Save 2 and pick all other...
This game is kind of a mess. Despite updating to patch 1.01, the game still freezes at the very later stage and you couldn't finish it. It lacks a lot of basic visual novel features too like message speed, skip read/unread message, auto-read, logging, etc. Gameplay is alright at first but it...