As always, first many thanks for again un update!!
To test I added just one directory with a multipart rar movie with an .nfo file with an IMDB ID.
I hit "scan for new movies" and the movie is scraped and the .nfo file created perfectly.
I hit "scan for new movies" again and would expect MC to say "0 movies files found", but it will re-scape the movie (which we just scraped).
This behavior is only with rar files.
Edit: and when I enable "rename non compliant .nfo" the above behavior results in the existing .nfo (which is good) to be renamed to .info.