Originally I thought you wanted the edit window to scroll left and right. Now I realize you wanted the cursor to move.
In Preferences, I set the Ctrl-Left and Ctrl-Right keys to do Editor/Word Left, Editor/Word Right. Personally, I was surprised I needed to set them, as I thought they were Windows standards.
BTW, version 6.0.4 is available, if you hadn't noticed. It fixes some minor problems, including a Find & Replace bug.
Best of luck,
Stew