Based on this tutorial about using chroma key and greenscreening, it seems it takes three video tracks (VMS 7 Platinum) to create greenscreening. But when I follow this tutorial, I lose the visabilty of my other clips on the video overlay track when perform the step of clicking on the parent/child button.
http://www.sundancemediagroup.com/articles/vegas_movie_studio_platinum/garbage_mattes_in_Sony_Vegas_movie_studio.htm
Is it common to have the whole video overlay track affected by clicking the parent/child button even though you want it to apply to a specific clip?
Is there another way to green screen that doesn't present this situation?