As far as binding data to the chart is concerned, see
How to add data in winsample chart control[
^] from a similar previous question.
There is an article here on The Code Project for Bezier Curves
Bezier Curves Made Simple[
^], which may give you some ideas if nothing else.
A quick search has revealed several libraries that claim to implement non-linear curves. I can only suggest that you search for yourself and have a look at some of them.