test.cs

using TXTextControl;

using (TXTextControl.ServerTextControl tx = new TXTextControl.ServerTextControl())
{
    tx.Create();

    // Add a paragraph to the document
    TXTextControl.Selection selection = new TXTextControl.Selection(0, 0);
    selection.Text = "Hello, Office Open XML!";

    // Set the paragraph format
    selection.ParagraphFormat = new ParagraphFormat()
    {
        Alignment = HorizontalAlignment.Center,
    };

    // Set the font format
    selection.FontSize = 240; // 240 twips = 12 pt
    selection.FontName = "Lato";
    selection.Bold = true;

    // Apply the changes to the document
    tx.Selection = selection;

    // Save the document
    tx.Save("results.docx", TXTextControl.StreamType.WordprocessingML);
}