Sorry but I cannot accept that. Either we can trust CCleaner to know what it's doing, or we can't - period. You can't just tell the user to make up their own mind which registry keys are safe to delete. As a user who recently has his new Windows 10 apps trashed, probably due to CCleaner removing something it shouldn't have, and by the way it took two Microsoft tech sessions to fix the problem (yes two), I feel quite strongly that Piriform needs to get it's house in order regarding Windows 10.
I agree with Luca B, users like me have come to trust CCleaner based on it's 100% reliable performance in the "old" Windows 7, but it's a new world now and that trust will quickly be lost if this is not sorted and fast.