Florian Sepp posts a little tutorial showing the use of his Fs Preview Render for Cinema 4D which allows you to create previews right in the pictureManager without the need to change render settings.

fs preview render is a python script for cinema 4d, it renders preview pictures in the picturemanager without the need of changing the render settings

FS Preview Render is written with Python and renders in the picture viewer without saving anything, and is able to render things like motion blur by changing the render settings temporarily to create the rendered image. This will allow you to test quickly if all your buffers and layers are working correctly in Cinema 4D. The latest iteration of FS Preview Render is 1.53, and adds support for the Cinema 4D Physical Renderer and is compatible with R13 and R14. Check out the FS Preview Render for Cinema 4D here.