I'm using a dual screen setup with NVidia drivers.. I noticed you have Dual Monitor option but those are for some reason ghosted in my XNView. Is this because I'm using 'Horizonal Span' and not 'DualView' in my nvidia options?
Because I really would like to have the ability to go to fullscreen on one monitor and not having the image centered on both monitors which I think is what those options allow you to change.. If that's not the case.. I would like to submit this post as a feature request

Keep up the good work..
Cheers,
wOLV.