how do I control "partial" mapping across two monitors?

[frueter]

Hi,

thanks for the work you put into this, it's really helpful!
Just trying to figure out if the gui allows to define "partial" mapping or if I have to crack open a json or other config file and punch in some numbers? Once I chose "Partial..." in the screen dropdown inside the mapping tab, I expected to get some widgets to allow for numeric inputs (or even some sort of interactive input).
I have two monitors and would like to map the maximum area of my wacom to full screen height as well as 1.5 monitor widths (i.e. I'd like the second half of one monitor to be outside the wacom mapping.
I can't find a way in the gui to do this.

Cheers,
frank