It tells the widget whether or not to capture mouse input. If you set it manually, it must be disabled manually otherwise it will go screwy when you try to open another UI element(inventory and the like).
Ok, so everything is set to 1? Move everything you don’t want to be clicked on or doesn’t need to be clicked on to 0 or a negative number. Make sure that none of the elements you want to be clickable are disabled or set to hit test invisible… the DevKit has issues when it comes to UI things, it may have changed things without your knowledge, it certainly did to me.
-WM