Sounds great Ribis!!
Wait... I do not exactly understand what this does?
If you do not need to login (to facebook) when starting the app, but the app can post highscores and have facebook profile data? From which user does it sends the highscores?
Do you have any tutorial, demo, manual or something?
I was making a manual that I almost finish...
You will play the game inside the canvas of facebook (canvas app) like farmville or some game like that... (or in your website)
the problems of the facebook plugins of construct2 (or similar) are that, when you start the application, and after the app is loaded (after the construct2 loading) you have to click a button to get the permission of the app,and sometimes you have to reclick or refresh the page... also, with the plugin you have to make all of the event in contruct2 and that's sound a little bit complicated... because if you want like hi-score of your friends , achievements...etc you have to make a lot of call with the plugin.
With my method, when you go to the app of facebook, at the start (before the game) the user accept the permission (just one time) and later, will load the game like all app and while the game is loading, the app has already al data you need for making your game because I did all in php outside from contruct2.
you can get your profile inside construct2 and you can use for save in a database ( I made a script that do everything outside of contruct2) and you can get the hiscore of your friends who use the same app (or all scores from the users facebook, but you need a database for that)
also the hi-score if I remember is posted in the games feed like game achievements etc....
example:
in candycrush, you can see in what level your friend is, I can do the same, but for these things I have to make a specific script for your game, or explain what you have to do...I can use the facebook data for making your game better, for the game I already make : score, achievements, story (if for example a user find some object in the game, the game will post in the gamesfeed the story) like in candycrush when the user do a special combination and you can see in the gamesfeed