This is a file that will be required to play After the Fall 3 and Melenis's Revenge! (Melenis's Revenge will be released soon...)
Place it in this directory:
C:\Program Files\Triumph Studios\Age of Wonders\Release
(same for Medieval Masters users exept instead of the 'Triumph Studios' Folder it will be named 'Take 2' then there will be a Medieval Masters folder)
Thanks to Tekk Zero for pointing this out.