According to OP:
Okay, so there's a little bit to talk about before I officially release this module. I got a bit caught up on making it great instead of focusing on the simplest possible implementation. With that being said, there is just too much here for me to realistically bug test everything, so I'm afraid you're stuck with the version that potentially crashes a lot. With that said let's go over what we got.This only works vertically at the moment, and only goes down on the lowest cell on the grid and the top cell of the grid. It should reset the cells to 1, 1 after loading into the character select, it would be too complicated to implement otherwise. When playing co-op, players on a team must select in order and can't control otherwise; again, it would be extremely difficult to implement otherwise. Assuming you don't do anything else, if 2 players are choosing on different sides, player 2 can navigate the menu but the grid won't move up and down until player 1 selects a character, in which case it will swap over to the other player. This module is meant to be plug and play; you don't need to touch anything in the system.def to make it work; it just takes the variables from the regular system.def. There are 3 system.def parameters you can add, though. slide.time, will make all the grids gradually move up or down as the slots are changing, making a smoother visual. Defaults to 1(instant) if not used

As for the other 2 paramaters, I thought the way it handles the character select by default is a bit rough, I was debating whether to do one roster that moves for one person, how it is by default or just splitting into two rosters. So I decided to do both. Adding p1.pos and p2.pos will make the grid appear twice, starting where it is placed. These are exact duplicates of the regular grid. This version of the select screen only appears if you call this in the system.def AND if it is a menu in which 2 players are on different sides, otherwise it reverts to the default. I thought the idea was cool in my head, so feel free to go wild with that. tldr: have fun, it will probably crash, module is live now