Magix changed Vegas Pro 17's identifier from "sonycreativesoftware" to "vegascreativesoftware", so many old version third-party FXs can't be loaded, such as Ignite Eexpress, HitFilm Movie Essentials Pack, Ignite Pro 4.0 and so on...
Here is the repaired files of HitFilm Movie Essentials Pack, place them to "C:\Program Files\Common Files\OFX\Plugins\HitFilmMovieEssentialsPack.ofx.bundle\Contents\Win64" and replace orignal file.
I just have the trial of HitFilm Movie Essentials Pack. Maybe someone who has the license can test it.
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I have removed the modified files, because these modifying breach the FXHome license agreements. But the reason why VP17 not load these plugins should be known.