Hey there,
Is it possible to import a c4d intro into unity and then run an build it with the rest of the game in unity. So when I start the actuall game, i want the game first to show the video and then the game
Yes, look at this page in the docs:
http://docs.unity3d.com/Manual/HOWTO-ImportObjectCinema4D.html
Unity supports C4D. But the importer alone does not automatically make your C4D an intro. You have to make the scene with the C4D animation your project’s first scene, or change to the C4D scene manually if you have another first scene (e.g. a pre-loader), and finally, write code to trigger a scene change away from the C4D one to your game’s main menu, or whatever should show first in the game after the intro.