At first I thought the movie looked promising, but then I grew annoyed that perfectly good Canadian stories have to be told by Americans and acted with English and American actors. Cultural Misappropriation.
In any event, the trailer for the movie can be watched here: https://www.youtube.com/watch?v=tCJO6Ax_ev8
I won't recommend it. But if you're curious as to who she was you can read the wiki: https://en.wikipedia.org/wiki/Maud_Lewis, or watch this old CBC biography: https://www.youtube.com/watch?v=xIr8PAO0RSA or a NFB short on her life: Maud Lewis - A World Without Shadows.
(Maud Lewis's hours in Nova Scotia, now in a museum)
(One of Maud Lewis's many cat paintings)
And then there's this: http://www.ctvnews.ca/entertainment/maud-lewis-painting-found-in-ont-thrift-shop-bin-to-be-auctioned-1.3342494 and this: http://www.cbc.ca/news/canada/kitchener-waterloo/maud-lewis-painting-new-hamburg-thrift-store-auction-bids-125k-1.4084862