Sorry for being a little vague. I want to have a XAML UI rendered to a texture in game, but I want to provide my own mouse coordinates, so that for example in a first person shooter, the player could aim at and shoot a button. There is no cursor except the crosshair, which is fixed. I'm sure I could...

Considering using your framework...
Is there a way to override input so that I could do something like use a 1st person shooter's crosshair as if it were the mouse?