A quick note -- with the latest set up, the pointer appears to the north-west of where the stylus is placed (more north than west).
I've been tweaking things with xrandr to get mirroring to work so I suppose it's possible there's something weird on my end:
Code:
xrandr --output eDP1 --auto --primary
xrandr --output HDMI1 --auto
xrandr --output HDMI1 --auto --same-as eDP1
May be it's that "--same-as" part...I notice that the pointer won't move to certain areas of the Max 2 with this set up.
Edit: the invisble border issue was addressed by using calling xrandr with the appropriate output and --panning 2104x1560