I've searched and couldn't find anyone getting Conquer Online to work in 1680x1050 resolution FULL SCREEN without just scaling up the 1024x768 full screen view. This would require editing the client, and a problem would arise, too. This would make the screen size bigger, allowing you to view more things and players on the same screen, and if you would try to jump at the side of your screen, it would say you cannot jump that far.
But any attempt or success is welcome! Let me know if anyone got this working.