I can't render videos: after i export the composition in the render queue, modify settings and i click "Render" it will render only the first frame. Any solutions?
It's impossible to say what is going on without knowing the details of your comp including the type of footage used, what you have done to the layers, and details of your workflow. We also need to know exactly what you did to 'modify' the settings in the Output Module or Render settings. If the render is failing what does the render log say? If you are getting an error message what does that say?
The most likely problem for a new user is that you've set the work area to 1 frame or you have added some kind of effect that is causing the render to fail.