Yeah I get all kinds of issues with trying to play games in windows native HDR mode. The one HDR game I have, Mass Effect Andromeda, doesn't play well anymore, and my non-HDR games have oversaturated weird color. So if I take it back to my old color settings (Chroma 444 8 bit), which I've done, I can no longer get MEA to switch into HDR mode when launching the game.
Sony 65" X850D, Onkyo TX-NR757, Klipsch 7.2, R-28F/2, R-25C/1, R-15M/4, R-12SW/2
HTPC: Corsair 800D case, Intel i7 7700k 4.5GHz (stock clock) Kaby Lake CPU, Corsair H100i CPU water cooler, ASUS ROG Maximus Hero IX mobo, Corsair Vengeance DDR4 16GB RAM @3000MHz, SLI EVGA 980Ti SC, Corsair AX1200i PSU, Corsair 360GB SSD Win 10, multiple large HDDs