For example, <h1> is imported as Heading 1 with font the following properties:

While MS Word imports it as:

Think of improving the message of the exception we throw if no data is loaded.

Workaround: set type explicitly:
<link rel="stylesheet" type="text/css" href="main.min.css" />

foreach (var style in this.document.StyleRepository.Styles)
{
    if (style.StyleType == StyleType.Table)
    {
        if (style.LinkedStyleId != null)
        {
            style.LinkedStyleId = null;
        }
    }
}

<ul>
	<li>
		<div>Text</div>
	</li>
</ul>

                BlockCollection footerContent = this.document.Sections.First().Footers.Default.Blocks;
                Table footerTable = footerContent.First() as Table;
                var cells = footerTable.Rows.Last().Cells.Where(x => x.EnumerateChildrenOfType<FieldCharacter>().Any());
                foreach (var cell in cells)
                {
                    cell.Blocks.AddParagraph().Inlines.AddRun();
                }