Excel doesn't support exporting to the ZBB format. You should check your software to see if it supports CSV, because Excel can export to CSV, a format widely adopted by various applications.
There is also no converter available to convert from XLS to ZBB format. The CSV export remains the only option that you could use.
You can check to see if the software supports CSV, using File > Open dialog then click the extension menu. If CSV is supported, then you can export from Excel and import on the one you're using.