How do I generate PDF from a website page - c#-4.0

Question

I'm using TuesPechkin library to generate a PDF from one of my website page.
Beside regular labels, the page is using Gmap for a map and Flot for a graph.
When browsing the page (report.aspx) directly everything is displayed correctly, but when using the code, the PDF is generated correctly but the graph is empty.
The code:
private void GeneratePDF(string reportID)
{
try
{
string baseUrl = HttpContext.Current.Request.Url.Scheme + "://" + HttpContext.Current.Request.Url.Authority + HttpContext.Current.Request.ApplicationPath.TrimEnd('/') + "/";
string url = baseUrl + "report.aspx?" + reportID;
HtmlToPdfDocument pdfDocument = new HtmlToPdfDocument
{
GlobalSettings = new GlobalSettings
{
ProduceOutline = true,
ImageDPI = 600,
ImageQuality = 100,
DPI = 1200,
Margins = new MarginSettings
{
All = 0,
Top = 2,
Bottom = 2,
Unit = Unit.Centimeters
}
},
Objects =
{
new ObjectSettings
{
FooterSettings = new FooterSettings
{
ContentSpacing = 2,
FontSize = 9,
FontName = "Arial",
CenterText = "Page [page] of [topage]"
},
ProduceLocalLinks = true,
ProduceForms = true,
PageUrl = url
}
}
};
byte[] pdfArray = TuesPechkinInitializerService.Converter.Convert(pdfDocument);
if (pdfArray != null)
{
string fileName = Path.GetFileNameWithoutExtension(Path.GetTempFileName()) + ".pdf";
string filePath = Path.Combine(Server.MapPath(#"\Reports\"), fileName);
using (FileStream fileStream = new FileStream(filePath, FileMode.Create))
{
fileStream.Write(pdfArray, 0, pdfArray.Length);
fileStream.Flush();
fileStream.Close();
}
}
}
catch (Exception ex)
{
LogHelper.Log("Exception at GeneratePDF:", ex.Message);
}
}
The generated PDF:
The website graph: