If you created a new Country and new tournaments and you can play them in Manager Mode but not in Tournament Mode this is the reason:

FIFA shows a country in Tournament Mode only if: at least one of the tournaments related to the country has a tournament id lower then 96. So you have two possibilities:

1) Assign your tournaments to the rest of world

2) Change the id of at least one tournament for the country to 96 or less

You can do both in the tournament page.