Many have tried various methods to set the SRL, but the KDP setting always overrides your own.
Well, there's one way! You can always set the SRL at page one, chapter one. That works every time.
Good point. I'll have to try that some time and see whether it then opens to the cover
In general, I've found that not setting the SRL at all gives me the desired results; i.e., the book opens to the cover. This is for books not in Kay Yu, though. I suspect the KENP-counting system messes it up.
Yes, books with no SRL often do start at the cover -- about three-quarters of mine do. I'd forgotten that. (I long ago gave up trying to set the SRL.)
The behavior is different in the actual book. There it tends to be where Amazon wants it: page one, chapter one. If asked, Support will explain that that's what readers want, but I suspect the real reason is that Jeff Bezos doesn't want to pay 40 mills each for the title page, TOC, and all that.
(Don't trust KDP to publish a print edition. Don't trust CreateSpace to publish an ebook. Each does one thing well and the other thing poorly.)