How to use cloning effect if the clips are overlapping themselves? I have tried to combine two video clips, but it feels impossible. In the first clip there's one character running around the screen. In the second clip the character is just standing (still being animated however) and the first clip's character should be running around him. When I tried to use the basic cloning effect by using a mask to the second clip, the first character simply disappeared from the screen when it reached the mask of the second one. How do I combine them so that the first character won't ruin the scene?! 

I'm using Sony Vegas Pro 11.
If the character runs in front and then behind the other character then either a depth map or a manually adjusted mask is going to be necessary.  I'm unfortunately an After Effects guy, so I don't know how you would do that in Vegas.  

If nothing else, you might be able to creatively do it by putting one layer of the character running around on top and another layer of the character running around underneath the character that is standing still and then cutting back and forth between them.  

That is of course assuming that the animations have alpha channel support and that Vegas properly interprets the alpha channel.