While -Dj3d.rend=d3d gets it minimally working in the ARM64 case, I defer to your judgement.
Getting the installer to automatically set it up right would be magnificent. The less the OS does special, the better! If you go this route, please post here when the new installer is up.
As for high-DPI, yes, I believe that was the combination of settings I tried...but I'll try again. It's been a while. (This is plain high-DPI trouble, not ARM64-specific, so I'm not particularly worried about it myself.)