I found the same problem whith NPOI 2.0.1.
If I use sheet.SetCellFormula("10 * 0.015"), the result is "10 * 15" when the correct is "10 * 1,5".
If I use sheet.SetCellFormula("10 * 0.015"), the result is "10 * 15" when the correct is "10 * 1,5".