[Carnigg]

@mikeSiLVO thanks for your response. The MPAA ratings that I can see are

Australia:G
Australia: PG - no space between : & P or you get G
Australia:M
Australia:MA15+
Australia:R
Australia:R18+

There should also be 

Australia:CTC
Australia:X18+

Although these aren't contained on any of the movies I have. You can see the full set of classifications here Australian Classifications 

As I said earlier I am now using EMM to scrape certifications, I should note that this program is not using the 15+ & 18+ but they are being displayed in the rating description and picked up in the certifications that is being picked up by Kodi as MPAA, if that isnt confusing things. If it is just disregard.

I also read earlier in the forum that where there is no rating it is utilising the previous rating rather than setting it to NR (Not Rated), which I assume is happening for everyone.

Thanks again for your time