[vbat99]

 I would like to be able to change naming: for instance if Media Companion's default for disc art is "movie name-disc.png" I would like to be able to change it to whatever I like such as "discart.png".

On Movie Preferences, Artwork Tab, there is the option to "Save Fanart.TV artwork as <moviename>-artwork". Uncheck this option to have the Fanart.TV artwork like "discart.png", "logo.png" etc, saved without the movie title prefix.

Media Companion puts an nfo in all movie folders, one's it can't scrape and tells you in the log and with other programs if they can't identify a movie for instance because the years wrong it will tell you, allow you edit it and re-scrape.  In the end though the other programs do not leave an nfo in the movie folder if it can't be identified. The incorrectly left nfo fools KODI into thinking a different movie is there.

MC doesn't give the user the option Mid-Scrape to select a different movie Title. MC is trying to get higher accuracy and automation. Which is why the nfo is saved when no movie is found.
MC can't determine if the incorrect movie is found, I don't think any media manager or Kodi can guess that the wrong movie was found.

Which is where checking after the scrape, is standard procedure.
But, if you want no nfo, then look at Movie Preferences, Scraper tab, at bottom middle. Check the option "If failed scraped, do NOT save an nfo file!"