I checked the INI files form the same build, theres no apparent tag that triggered it.
My best idea is this but havent tried it yet;-
SelectPortrait= checks the Mapped Images files for the cameo. If the specified cameo isnt defined there, AND the window uses W3DCameoMovieDraw, then the game will then look either in the Video.INI file for it (more likely) or directly in the Movies folder.
Like I said, havent tried it out yet, but given what WAS removed from the game over the months it would be weird if this didnt work somehow given that all seems to be there.
It may even work with (or even require) a bik movie instead. Either way it looks like the movie needs to be 90x68 pixels to fit.
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