Enigma works by encrypting and packing content into a single binary (which is why its so large). You can use "Enigma Virtual Box unpacker" from here to unpack it yourself:
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The Enigma binary will run just fine on Windows (with loss of performance, of course) but this is not an option for non-Windows users (usually it just straight-up crashes).
Its been a while so I don't recall the exact scenes. Using NW.js however, you will see errors on the console about missing files. This is because Enigma intercepts and redirects filesystem operations, the files do not exist on disk. I think RPG MV even errors out and displays the usual "retry" prompt.