just have a look at the file Data\HowToMod.html and the file Data\Tour.ini to see list of tournaments and how to edit it.
So yup, you can add any tournament you want to the existing ones without trouble.
If you add tournaments, usually, you'll have to start a new game.
You don't have to add players, but if you add a lot of tournaments, some of them may have a not full draw (but the engine can handle it).
The game can let you choose between up to 6 tournaments on the same week, so if you put more than 6 in a week, you couldn't choose it and play them all within the game, but CPU players could still join all of them.
== Mana Games ==
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