When an Extension Module has been provided by Conquest Software, whether new or an update. Install it with the Management Console - Product List - Extensions category:
The Extension Modules available for your organisation are listed. Select the latest version of the one you want (Picklist) then click the ‘Download’ button, which changes to the ‘Install’ button, to click too.
Note: The nature of Extensions, demands that you must test that they still work on the new version of Conquest III.