This file will let you play with nations which were unplayable until know. To know which nations are now playable and how does it work, please read the following topic : http://fmhvibe.co.uk/index.php/index.html/_/sports-i/new-nations-playable-r416
The second file (More Nations Playable) contains more nations playable for each countries. These are not new nations but already existing nations which are playable for more countries. For instance, Belgium was not playable for French Leagues only, now it is. The only new nation which was added automatically is Denmark for few leagues.