Haines

Your summary ...

"The world is in flux. It consists entirely of continua or processes.  By acting on it out of desire or instrumentally, we impose limits of self on this natural flux. This brings frustration and pain. The way to avoid it is  with wú wéi, a "mindless" action without desire or goal. This allows our actions to accord with the flux of the world about us, and so alone provides satisfaction."

Not way off but I'd rephrase it.

The space-time world would be forever in flux. Attachment to it will lead to suffering because there is nothing permanent anywhere. In particular, our attachment to the ego and identification with it brings suffering. The ego would be impermanent and would not really exist. In short, we will experience suffering if we do not see the true nature of Reality.

The way to avoid this suffering would be to transcend the ego and its desires (as represented mythologically by the Crucifixion of Jesus) and to be able to stand back from ones suffering and, as it were, not take it personally.

Many people who have suffered great pain have found that there is a place in consciousness where the pain doe not reach, or, rather, does reach but only as a phenomenon to be noted, not as something that one would want to participate in or own. This is what Buddhism points us towards, this disassociation with 'me' and 'my' suffering. (I had this learning experience as a teenager - and remain very grateful for it). 

For an ultimate view there would be no suffering and nobody who could suffer. This would, of course,  be a purely conjectural theory for a non-practitioner and of little use to them. It would be fact of life for a 'realised' individual. It would be to some extent an experienced truth for the average person who does a bit of practice and perseveres. Practice would 'make perfect'. 

Wu wei would be a natural response to the situation once we know what the situation is, but may not be directly relevant here. As Ramesh Balsekar writes, 'Why carry your luggage when you're being carried in a vehicle?' (His book The Ultimate Understanding is  good on this). 

This is a poor post. My head is not yet in gear. I might go check my database for a clear statement from a Buddhist.