Noob problem: Rotobrush layer wont render
This is probably some really basic oversight on my part. I've rotobrushed part of a video to get rid of the sky in the background. And set the 'work area' to that part. Apparantly that's a layer. And then there's a composition.
Whenever I try to render the video, it renders the composition instead of the layer and the result is a video with nothing but a black screen and the sound. What am I missing? I figure I somehow have to integrate the rotobrushed layer into the composition? How do I do that?
Any help would be much appreciated. 
