PUZZLED??

Good Morning,

I am attempting to export a frame of my slide show into an mp4 using quicktime in imovie 11... I have been successful in doing this until last night. I woke this morning, moved Imovie project folder from my finder to desktop...cleared imovie cache files from imovie cache folder, even went to library and cleared .plst and locked .plst and restarted puter... I am able to create the mp4 of the image(s) that I am importing for a cutaway piece to main slide, even able to export main slide to mp4... both are timed out at 34.9s... I put mp4 of images into main slide and use inspector and position pnp into place, preview it, settled go to export using quicktime, then the DISAPPOINTMENT... have done this several times without successfully getting it to export, NOW WHAT??