The DSR is something the video card does... the game will follow that.
Try some settings, like factors at 3x and smoothness at 33%, I saw a nice difference in CloD mainly, smoother pictures etc...
Just try and see what works for your setup, mind you, I guess too high a settings may make your video card struggle...
As far as the other issues:
Found this: here
Hi Johann, This TV only supports HDMI 1.4, and that's what I'm using. It does not support HDMI 2 and that's why it only has 30Hz refresh rate when in 4K, Thank you.
But, there is some firmware update that could be of help: here
Found it all in this thread: here
Hope it helps ya!