Running NOLF on Windows 10 on an external 1920x1200 external DisplayPort display positioned above a 1920x1080 Intel laptop screen, I can't move the game cursor to the bottom ~15% of the external display ; instead the Windows mouse cursor appears on the laptop screen below.
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Right after you set resolution your mouse will only move in the area it had in the old setting until you restart the game.
Just use your cursor keys to go to quit and launch the game again. Everything should work just fine then.
(Make sure that your run both Nolf.exe and Lithtech.exe as administrator to be able to save settings)