Eureka!

After literally years of frustration, I finally found a fix! I have confirmed with 100% consistency (so far) that if I do a very small 'area render' it resets the UI -not values, but function. The only drawback are the renders that I have to then delete (or empty the cache). But it's still a whole lot better than having to restart every minute or so.

Well, OK, It doesn't actually 'fix' the problem, but it's a majorly useful workaround.

However, if anyone reading this thread can deduce the culprit in the glitch, I'm still down for a solution. (other than upgrade. I have upgrade fatigue)

Thanks all.