Hello Ian,
The layout is saved by Windows, not our drivers. That's why removing/reinstalling have no effect.
If 2|3 does not split when you save the change of layout, then your layout may have been corrupted.
Here is how to force monitor rediscovery in Windows. I advise you plug back one monitor at a time.
http://support.displaylink.com/knowl...fy-numbers-are
Kind regards,
Alban