Do this.
Open up the roster .rar. Go to the standard folder, then to roster files, then database. Put all those files in your MVP/data/database folder, and click Yes when asked to overwrite. If you have the original MVP 05 installed, that's the roster version that will work perfectly for you.
The models.big that we talk about is a collection of hundreds of custom cyberfaces for players for the game. I suggest you just get a feel for the game and its files using the standard version first, and then when you know how the file structure works, you can download MVP 07, and all the corresponding addons for that.