Are you sure you're talking about the same thing? Screen filter is available on any version. This topic is about the brightness control setting that allows NTR to lower brightness much lower than factory settings, which to my knowledge, is only something available on 11.3 and lower.
I guess im talking about something different then, but regardless im unable to use the screen filter unless I set the option before I launch an application.
I don't see the menu option for brightness control anywhere in the NTR settings menu, is that option removed if you are running anything later than 11.3 or something similar?