I have two monitors, and I just tried to switch X-Plane from one to the other using the Settings>>Monitor Configuration panel without any issue. You might have to set the center monitor as your main one via the X-Plane settings, or maybe through the Windows/Mac/Linux monitor settings. As I use Windows, I started through the Display Settings in Windows. You just have to play around with the settings a bit, with patience. Let us know how you fared.