In this video you can see how to prepare an Excel file before using it on SpreadsheetWeb..
Hide any worksheets that should not be included in the user interface of the application. Also, hide If there are data rows and columns in the visible sheets that should not be included in the user interface. SpreadsheetWeb will analyze the visible parts of your workbook and break these elements down into web controls. Depending on their location and their dependencies in the formula structure, it may detect them as individual controls (such as textboxes or dropdowns), or it may combine them together into a single grid control. If turned into a grid control, the formula cells will block data entry by default, but their values will be calculated in the final application. If you want to control which cells should be individual controls and which ones should be combined, simply create them as named ranges. If you have charts and label cells, you can leave them as-is and let the system handle them.