How manually create Excel Template with Sections?

Hello, I investigating Excel Templates..... I wonder, how "Import Template" works?

Table 14919 :

LOCAL LoadSheetSectionHeights(ServerFileName : Text;SheetName : Text)
List := ReportBuilder.GetReportSectionHeights(ServerFileName,SheetName);
FOR I := 0 TO List.Count - 1 DO BEGIN
  SectionInfo := List.Item(I);
  ExcelTemplateSection.INIT;
  ExcelTemplateSection."Template Code" := Code;
  ExcelTemplateSection."Sheet Name" := SheetName;
  ExcelTemplateSection.Name := SectionInfo.Name;
  ExcelTemplateSection.Height := SectionInfo.Height;
  ExcelTemplateSection.INSERT;
END;

I want to Import my own Template, but how NAV find out my Sections Height?
How can I mark my sections in my excel template file? So NAV could properly import it.

Any link on MSDN?