I took a quick look and i think it might be a bug. The text showed up again if i switched the "UI" Layers Parallax to (100,100). But when i switched to that, the texts weren't moving, just staying there.
I've just launched the Ghost shooter example from the r76 (bottom left of the start page "Project examples" section), and set it up to fullscreen on (scale mode). I can see the score text in FF 9.0.1 and Chrome on preview, everything works fine, even resizing my browser during the game.
Make sure that your text objects are on the UI layer and that parallax is 0,0 (this is is the intended way).