I believe you would have to have an external server or something to send highscore statistics safely to Kongregate. Do not try to use the serverside stats stuff from your game because that just gives away private information (game api key) which can be used to falsify high scores.
Yes but I mean is there an application to integrate automatically games from Kongregate to Facebook?
I saw that some facebook games come to Kongregate but what about Kongregate games to Facebook?
I believe those games you saw used iFrames (MMO games for example), so perhaps it might be possible. I’m not terribly familiar with facebook (or their API or kong’s integration with it)