Hi,
We tested your code and it seems to work fine here.
The header and main contents are converted
almost independently. Specifically, it is not true that the headers are converted first. The header are converted and then outputted in the header area, the main contents are converted and then outputted in the main content area. So if these two areas overlaps, then your header and main contents will overlap. Or even if these two areas do not overlap, but the header is too big and overflows the header area, it can "spill" into the main content area and to overlap with the main content.
You would use HtmlToPdfOptions.OutputArea to set the main contents area. You would use HtmlToPdfOptions.HeaderHtmlPosition to set the top position of the header area. The left/right position of the header area is the same as OutputArea. The bottom position of the header area is open (thus it can overflow to the main content area if the header is too big).
The only connection between the header area and the main content area is that the header HTML would use the same zoom level as the main contents. So if the main content has been zoomed out, then the header HTML will be zoomed out by the same level as well.
If you still have problems, please try to isolate the problem into a separate test project and send the test project to us. Once we have that we will be happy to investigate further. See here for more details on sending test project to us:
https://www.essentialobjects.com/forum/test_project.aspxThanks