I did more tests.
The problem was on a layout with 6 custom views (not too much complex, only 5 simple components) and the Animation Duration set to the default 400ms.
Then I tried a similar layout but with 6 simple panels. With this layout it seems ok, but I'm not sure, because the animation is too quick; so I changed Animation Duration to 1000ms and it works as expected.
If I increase the Animation Duration to 1000ms in the first layout, with custom views, animations start, first time and next.
I think using 400/500 ms animations seem to start only first time because app takes time to create the custom views (but, correctly, I don't see their creation on screen)
Thank you