I played a game where I made a very funny kill. I went to the Theater to try to save it to show to some friends, however, I have no recent films to watch. Please help before it is too late.
Did you check your temporary files? All of your recent mm show up there and you have to download it to your Xbox.
I’m having the same problem.
its differant to all previous halos, suprise suprise, you need to go start, down to the bottom bit and go and find tempory files and clips, sorry cant remember all the bits, doing it off memory, and you should find em and then press y i think and save it 
hope this helps
They instead of making it nice and easy they made it so you have to download it first.