Lilian,
I solved this problem on my own system, perhaps this will solve it on yours.
In the camera view window(s), there is a pull down menu between “display” and “view” called “Filter.” Look through the options there. make sure that “Splines” is checked and viewable. Once I did this, I could see both splines and the objects inside of a mograph tool.
Hopefully, that works for you, too.
Good luck,
George