WCT allows use to select 2 ranges in Excel and compare their values. Ranges may have different size. Use Compare Ranges on the Spreadsheet Tools tab:

In this dialog you should select which range is old version and which is new:

If your ranges has database structure, please read topic Comparing Database Values to find more information about Compare Database Values options.

When ranges are selected press Compare button. Now WCT has enough data to start comparison.

When the comparison has been completed, you get the comparison report, like this:

On this comparison report you can browse list of changes, copy, delete and merge values. All of these features are described in the Working with comparison results topic.