I have two sets of video clips that I'm editing (on the same track). I edit the first clip (add effects, transitions, etc.) then I edit the second clip (add effects, transitions etc.) but when I go back to watch the first clip parts of the second clip are in the first clip. Why is it doing this? How do I fix this problem? Also, whenever I add the cookie cutter effect to a clip and try to edit/move the sliders they don't move. Why is this happening? How do I fix this?