One of my favorite terminator features is how the focused window had a red titlebar. This makes it very easy to see which pane is active.
However, I recently switched to a dark gtk2 theme (I'm running lubuntu) and now all titlebars are permanently black.
I've tried tweaking the following setting (it still shows red), with no effect:
right click terminator > Preferences > Global tab > Titlebar section > Focused terminal Background
The "Font colour" (i.e. foreground) and other settings work fine.