PDFsharp & MigraDoc Foundation

Hi,

I am trying to draw charts in a PDF using MigraDoc and PDFsharp. I have started modifying the example HelloMigraDoc (WPF build, version 1.32).
The problem is that when I try to draw ticks and/or gridlines for the x axis it draws one per each y value (and I have thousand of y values!) , and I am not able to change the majorTick value. It does work ,however, for the yaxis.
I have been able to label just some points in the xaxis adding manually those XValues and the rest as AddBlank(); but now I need to draw some gridlines and I cannot find the way to do it.
I have tried the solution proposed at: viewtopic.php?f=3&t=408 but it does not work either...

Could you provide me with a solution?
Thank you very much in advance!