You can now use the object for your computations. In the list of fit parameters there will be one parameter named 'q' only for this object. Select q and set the parameter range to 0 ... 68. Click on 'Slider to generate a moving slider window which lets you easily change the optical constants of the object. You can fit the parameter q like any other model parameter.

Since you put a lot of effort in getting all the data into the new material object it is a good idea to save the configuration that you used to generate the object. In addition, you should save the new material to the database for future use.