In addition to the fast document generation, the SpreadStreamProcessing can be adapted to import documents significantly faster than SpreadProcessing.

When a cell value contains commas or new lines, they are not escaped on export to CSV and single value is exported as multiple values.

Workaround: Escape the value manually. For example, use the following extension method to set string cell values:
internal static class CellExporterExtensions
{
    public static void SetValue(this ICellExporter cell, string value, SpreadDocumentFormat format)
    {
        if (format == SpreadDocumentFormat.Csv)
        {
            if (value.Contains(","))
            {
                // escape all quotes with double quotes
                value = value.Replace("\"", "\"\"");

            }

            // enclose all values within quotes
            value = string.Format("\"{0}\"", value);
        }

        cell.SetValue(value);
    }
}

Available in LIB version: 2017.1.403

The UTF8 with BOM encoding should be used to properly preserve the different characters.

Available in R3 2017 Official Release.

Provide a way to measure text on different platforms so the user can pass the cell value and SpreadCellFormat and get the size of the text in pixels. This way we will be able to implement auto-fit to width functionality (AutoFitWidth), at least for the .NET Framework implementation. It will be able to measure the width of all cells in a column and set the value as column width in pixels.

When calling SpreadExporter.CreateWorkbookExporter method and referencing Trial assemblies an exception is thrown: System.ArgumentException: 'An item with the same key has already been added.'

This behavior is observed both with the NuGet packages and DLLs.

It is not observed with Trial DLLs version 2020.3.1019

If  row has a property set on it (for example "hidden" or a style), but it does not otherwise have any cells in it, the application might run into an infinite loop. The xml will look like this:

	<sheetData>
		<row r="1" spans="1:2" x14ac:dyDescent="0.35">
			<c r="A1"><v>1</v></c>
			<c r="B1"><v>2</v></c>
		</row>
		<row r="2" spans="1:2" s="1" customFormat="1" x14ac:dyDescent="0.35"/>
	</sheetData>

The last row has formatting applied, so it is present as an element, but has no cells. This file (when the xml is not formatted) will cause an infinite loop on import.