What author changes are acceptable after paper acceptance in the camera-ready In a conference in the CS field, what sort of changes are acceptable from an author of a paper in the camera-ready version over the submitted version? 
Can the author add few new related findings?
I can't speak for all parts of CS, but I have seen authors improving theoretical results, fixing bugs (both bugs discovered by the reviewers and bugs not discovered by the reviewers), changing the presentation (both following reviewers' requests or not), and adapting experimental results to the latest version of a tool, and I have done so myself, and nobody has ever complained about it.

On the other hand, if you have any reason to believe that the reviewers would have preferred the submitted version to the updated version, or would have rejected the paper if they had seen your changes, you should probably not change it.