@k2121 yeah great news!
Little update on the GUI
(you can't set folders and you could enable/disable black/white level)Windows user can't click'n'drop MLV file in the field to get the path. I think it's not userfriendly to copy/paste path and filename..
So I decided to rethink how to process file. In my mind:
User creates a subfolder directly in Lightroom and paste MLV file inside.
User selects the subfolder and run the import (plugin detects pathname for the MLV and check if folder contains more than 1 MLV (warn user if > 1)).

Why I do that ? Two things I see:
Lightroom API doesn't have a File browser, so user need to copy/paste...
User could process entire path with same settings after conversion
Any suggestions ?