I copied the interposer files and the fg dll over to witcher 3 and it fixed the hard freezes there too that would happen when you would go into menues and such.
Well I only tried it for a few minutes but I don't get that huge lag spike coming out of the menu with frame gen on anymore so hopefully that is addressed for everyone.
The only problem I had with last patch was using frame generation and getting extreme fps drops everytime I opened and closed inventory or something similar