Thanks Dave.
I’m still having the same problem with all my layers in 3D, so I was waiting to have another computer to render the video again with a better video card (that’s why it took so long for me to answer. I apologize), since I thought that might be the reason why I’m seing like this my handwritting when I introduce Camera effect:
Even though I rendered it with a better video card and I have all layers in 3D, I still have the same problem. When I don’t use any camera effect this is how I see the board: 
Regarding the issue with changing camera effect in each of the layers, I´m still having trouble with that. When I use the camara for the first layer it does what I want. But when I want to change the effect for the following layer, it also changes the first effect in the first layer. I tried to use 2 cameras to avoid that, but it didn’t work either.
Cheers