Here, the same way you installed WP Configurator Pro. Just download the zip file you received and upload it into your WordPress Admin Dashboard. Go to Plugin> Add New> Upload New> Upload the zip file as shown here:
Install the addOn and then activate. After this process, check inside your Configurator Editing Panel. The “conditional icon” will show up on the upper right corner.
From there, you can now add conditions to your product configuration.