I've tested Tubeloc. With this I can indeed load succesfully another movie.
On the other hand, it's heavier then using SWFLoader. Hope to find a fix for loading different movies without errors.
And I still have question 1 open. How to provide a Fullscreen button in the (embedded) Youtube player?
OK, now I have the fullscreen button (added "?fs=1" to the videoId).
A click on this button won't do the trick but I have found a workaround. Added an transparant button above the Fullscreen button in the player, catch the click and perform a custom function.
In this function I define a Rectangle and do a: stage.displayState = "fullScreen".
But, almost there, I'm getting annoying scrollbars within my fullscreen modus!
The cause of this is that the fullscreen modus want to show all elements at the stage. But that is not what I want because I only want to show the region within my Rectangle.
Is there a way to remove the scrollbars from the fullscreen modus, and only show the part within the Rectangle?