I was more talking to Alex. Well musing as to whether or not it would be possible to add a parameter to the object texts for defining the font for the object text & whether or not it would be possible to use object texts on both menu & playable scenes.
As for what you said about narration texts. You are right that there is no simple method for displaying a narration text permanently but, it is possible by creating a loop using the jump to x action part.
display narration text 'some text...' for x ms (background text)
pause for x ms - 10ms
jump to action part #1
This would work in same way as object text, except you are using a loop to make sure text is constantly displayed. You would have to manually kill the loop at end of scene by quitting the action containing the text. Also because text is in a loop, it would display the new text based on current language on next loop.