At this stage I'm not sure. I sent a pm to another member who might have some ideas.
One other idea: Open up a new OSX user account & install LW within it. This should not be affected by other things & will not be affected by things from your present account. Set up a completely new location for it. I know Stief would recommend doing this & can help to find out what the issue is. If it works in the new user account then...
After this you'd tried everything I can think of other than going backward a version or trying the Beta. You could try the beta 4.3.2 You'll find a link for it at the bottom of your personal downld page. I might want to know how you have your prefs are set up but that can come later.