I also noticed its difficult to see if the map its on has a fair amount of detail (not black like your example screenshot). It would be nice to control the opacity of the entire hud more. I am using Galv's Layer plugin with parallax mapping, if that matters.
The opacity now works fine, but there's maybe a weird bug with the TP bar. I do set the switch to ON to make it not visible, and it works when the game starts, but after the first combat, the TP bar comes back and is visible again. Not sure if something isn't saving. I do not use TP in my game at all. Thanks!