Almost the same here, I always found it difficult to do what I wanted with these frameworks. I ended writing my own custom javascript graphing code.
I realized it is not that hard to do, you can get nice graphs out quickly without too much code. I also found teh resulting code to be simpler than the one from libraries. I suspect that a lot of the complexity comes from making things generic, or maybe (in some cases) the authors being unfamiliar with javascript?