Tried out the first new public beta of El Capitan yesterday. Mix Emergency 3.0.2 plays videos fine as far as I can see so far EXCEPT for the overlay function. Text, Image, etc are ALL jacked up and need some love. Also, any versions previous to 3.0.2 have messed up video playback. The output screens are cut into 4 different horizontal sections. 3.0.2 is the only version that doesn't do this.