I agree with bradnewsom to an certain point. It was very sure, that Windows 10 is coming. It was also very sure, that a lot of people will migrate to windows 10 very fast due to the fact, that it is free for Win 7, 8, 8.1 owners. Win 10 got after 4 weeks more than 75 million installations.
And yes, I am not able to go back to an pre win 10 driver, and I am not able to use Painter since the migration. But it seems, that the fault is (also) on Nvidias end. But I guess someone has to submit the error to Nvidia so they can fix it.
Long story short. It is a huge amount of time, that we are not really able to use a software for daily work. That new driver should be there last friday. Today, 6 days later still no driver or patch.