I've had a great deal of difficulty with getting smooth motion of cameras in Carrara. One thing I've done is to create a target object (in fact, I think Carrara has a Target Helper Object built in, now, but I just use a sphere that I move around, then make invisible before render). The target object can be moved, and you can keep your camera pointed at the object; you can still effect banking in the camera and such, but it will stay pointed at the object. It's kind of a wonky solution, but it does help to get rid of those wild movements that happen before keyframes. I'm hoping that they're able to make the animation in the next version of Carrara less bizarre. I'd love to be able to use easy-ease and easy-ease-in and easy-ease-out commands for the tweeners like we see in AfterEffects.