I’ve tried multiple combinations to save the settings. Obviously closing ISE before entering the ED.exe location manually or via the browse option were the first steps I took. But as mentioned, it never sticks. Either the file reverts back to the false location or the propper entered location isn’t saved at all and the directory location stays blank.
If you quit ISE and enter the path manually in HidMapperSettings then ISE will try to validate that path on startup. If the validation fails then ISE will disregard the path you’ve entered manually and instead grab the game installation path from the windows registry (the uninstall entries).
If you haven’t already done so – take a look at:
http://developer.tobii.com/community/forums/topic/infinite-screen-problem-with-the-standalone-elite-dangerous-horizons/#post-4251