Change color of bars depending on value in Highchart bar-chart with MVC3

I am using Dotnet Highchart with MVC3

I am currently working with a diagram that looks like this:

I am trying to modify my code so I can change color on the bars depending on what number they have. I also wonder how I can remove the button "Snittbetyg" as you see can on the image.

This is my code:

 public ActionResult OfficeStatistic()
        {
            {

                Highcharts chart1 = new Highcharts("chart1")
                    .SetXAxis(new XAxis { Categories = new[] { "Ödmjukhet", "Engagemang", "Kompetens", "Lönsamhet" } })
                    .SetYAxis(new YAxis { Title = new YAxisTitle { Text = "Betygskalan" } })
                    .SetSeries(new Series { Data = new Data(new object[] { 1, 8, 9, 6 }), Name = "Snittbetyg" })
                    .SetTitle(new Title { Text = "Örebro Statistik" })
                    .InitChart(new Chart { DefaultSeriesType = ChartTypes.Column });

                return View(chart1);

            }

        }

Any kind of help is appreciated.

Thanks in advance!