When I drag my video transitions (crossfade, for example) onto two clips, I am finding that they are not attaching themselves to the clip or clips. There is no space between the clips. The clips are AE links files. Some transitions do work between other AE clips on the timeline, and other times the transition only works on one AE clip. Plus, I am finding that the transitions are not sticking to some stock footage either. Any suggestions to get the transition into the timeline?