Doesn't AmberElec have Portmaster included? As a member of their Discord, I've brought a handful of GameMaker games to Portmaster and I actually have DOZENS of ports in the pipeline. And Mushroom Kingdom Fusion is on countless folks' wishlist, but the way GameMaker games are ported (GMloader) requires a "data.win" file and numerous other external files (OGG music, for example). And the only way that's possible is if Mushroom Kingdom Fusion is ported to a newer version of GameMaker. There's another Portmaster release, Hyper Princess Pitch, that needed to be ported from an older version of GameMaker before being brought to Portmaster (and before that the PlayStation Vita).
I understand that there is more to it than just switching to a more recent version of GameMaker.