Black screen but audio works fine in the finished product in WMM

So ive tried my hand at windows movie maker to make some compilations with the footage ive been getting off my xbox one. ive uploaded the clips to the skydrive and then dled them onto my HD. everything works while inside the program, i can preview and watch the entire film i made with no problems, sound and video work perfectly. but after i finished and saved everything, the videos are all black. i have saved the files as .wmp and .mp4 and both are the exact same deal. i uploaded the video to the skydrive and youtube and it is the exact same deal. ive been at this for 2 days now and understandably am extremely frustrated. any help would be very appreciated. im using what i assume is the newest version of windows movie maker since i dled it 2 days ago haha.