Almost there, pdmarsh. This worked for a triple screen setup in landscape mode:
UIs =
{
SpanAll =
{
x = 0;
y = 0;
width = screen.width;
height = screen.height;
aspect = screen.aspect;
}
}
UIMainView = UIs.SpanAll
It's not perfect, now the main screen is spread out over all 3 screens too. Oh well, this will have to do for now. Alternatively, one could fix the F10 lua code to use the correct aspect ratio.