@harkr: as far as I know Premiere is not able to export "real" FCPXML files. And as you see, you did not export a .fcpxml, but a .xml. This is a difference, and that is why you can't import into MLVApp. I've never seen a .xml from Premiere, so I can't tell how it looks inside. If Premiere really exports a fcpxml (but with xml ending), you could try to rename the file ending. But no idea if MLVApp is able to read it.
@jdana: Apple just presented the new models with M1 processor. None of the devs owns a ARM Mac, and there is no Qt5 (the used development environment) for Mac ARM processors existing. Both is a must have to be able to support it. If Qt5 ever supports this architecture is not sure, because they will start rolling out Qt6. And if Qt6 is really compatible, I can't tell either. Time will tell... but for now it won't be compatible, if I understood right. So for now I recommend to not buy a ARM Mac if you want to edit MagicLantern files. Maybe it works with the use of Rosetta2, but who knows.