"Paint S" program asked if I wanted to 'upgrade'. I said 'yes' but then saw I needed to make a purchase
From that point on it was impossible to get out fo the program without making a purchase.
I even tried a hard shut down of the computer and it wouldn't do it unless I had closed Paint
This seems a really screwy thing Apple have done to force people to purchase an upgrade
In the end I just held down the power button until the computer shut down
Is there any remedy to this in future?