Interesting about the Costa Rica coach! Here are the rules from the FIFA website which say the are not supposed to vote for their own players:
FIFA has been conducting the vote for the FIFA World Player since 1991, an event which in the space of a few years has become the most prestigious awards ceremony in the world of football. What distinguishes this award is the fact that it is the senior national team coaches of the FIFA member associations who are invited to nominate their outstanding players of the calendar year.
Since the inception of this event, the voting procedure has largely remained the same. Each coach names the three best players in his opinion and ranks them first (which earns the player 5 points), second (3 points) and third (1 point). However, the regulations state that coaches may not vote for players from their own team.
The number of coaches taking part has steadily increased over the years. Last year, 140 coaches participated, and this year another significant increase was registered as 150 coaches cast their vote.
The player with the highest number of points is declared FIFA World Player of the Year. He and the players coming second and third each receive a FIFA/adidas trophy.
FIFA's partners in this venture are the sports equipment manufacturer adidas and European Sports Magazines, a group of internationally renowned sports publications consisting of A Bola (Portugal), Don Balon (Spain), Foot Magazine/Voetbal Magazine (Belgium), France Football (France), La Gazzetta dello Sport (Italy), Kicker (Germany), Voetbal International (Netherlands) and World Soccer (England).