Did you get this sorted @FNP7 or did you return the machine>? Ditherig didn't have any problems installing on my XPS 15 with Intel Graphics 530.
I just wanted to check in now it has been a few monthsand say that this laptop has remained usable for me with Ditherig installed. It's the easiest my eyes have felt with a laptop screen for years! Again, I'm using the Matte 1920x1080 screen, no touch. Intel drivers are version 20.19.15.4483 and Nvidia drivers are version 10.18.13.6881.
Really hope this helps someone else! Did you have any joy @Gurm?