Build 3.0.0.85 of xlsgen ensures that what-if data tables from .XLSX files are preserved when updating such file.
This build also ensures existing what-if data tables from .XLS files are converted to .XLSX files whenever applicable.
As a reminder, what-if data tables is a mechanism for testing function parameters over a number of columns or rows. In Excel versions before 2007, this feature appears in Data / Table. In Excel 2007 and above, this feature appears in the Data ribbon then the What if analysis button then the Data table menu option.