I've attached a ZIP file with two XLS files, once generated by Aspose (_Asp) and the other generated by automating Excel (_Exc). As best we can determine the Excel file has the correct results. The Aspose file, on the other hand, has clear calculation errors spread throughout. Take a look at the Income Stmt sheet. The numbers from Excel look reasonable. The numbers from Aspose are wrong (look at the Income tax in O30, for example.) Then, if you select O32 and hit F2/Enter, it produces a completely different number, which is also incorrect. Many other cells in the model exhibit the same behavior.
We make the file by storing input values and formulas into a blank workbook. In theory, Excel should be calculating all derived values when we first load the workbook.