If you need to delete a row from the Account Spreadsheet, position your cursor on the proper row and click the "Delete Row" button on the Statement screen.  Selecting EDIT and DELETE SPREADSHEET ROW from the Menu Bar also accomplishes the same thing.

If you need to insert a blank row in the middle of the spreadsheet, position your cursor on the line below where you want the blank row, and click on the "Insert" button on the Statement Screen. Selecting EDIT and INSERT SPREADSHEET ROW from the Menu Bar also accomplishes the same thing.