Hey matriax hi.
It is not so difficult to reproduce a fade in | fade out effect . (five to ten clicks) just add a black sprite with the fade behavior (with the desired fade out and fade in time properties) in the top layer of your layout and call it twice, one on layout start for a fade out and two, just before you go to the next layout for a fade in .
You better add this sprite to a global layer with 0 parallax and 0 scale rate make the width and height match your window size and you are finish with the fade stuffs.
So IMO i think there is no necessity for a build in fade in | fade out "function" as long as a fade behavior exist.
Cheers.