Hello i am new to sony vegas and i need to add a croma key effect to a video i recorded. i have the vid on my pc and its good quality, but i viewed many walkthroughs and alls it says is to make another track with what i want and then add the effect to the first track with the specific color for chroma key. i do that and nothing happens. can anyone get me some help please. this is for a school project and its due monday. i have done this before but it wont work now.aghhh!