I would also like to hear some answers to this. Using my Atrix, I am having this issue. I have a laptop, a PC, and a ReadyNas (network attached storage device) all with movies and other media on them which none of the movie files will work. I think I had an mpg work once. Most of my files are .vob .mkv .mt2s and some .mpg. I was hoping to find a different app that might have better decoders because I'm thinking that might be it's problem.
Thanks.