Yes. I've just answered a similar question here: Re: Inputting videos in slideshows Although that question was about overlaying a video on a static image the process is the same for a video overlaying another video. Using tracks and position / scale controls you can include many PIP's.
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And don't forget to work in Timeline mode so that you can have each video on a separate video track!
Here is a look at PiP in PrE 4.0. PrE 9 will be almost identical, and the trial no different.*
As has been mentioned, Timeline View Mode is where you want to be editing in, and not Sceneline View Mode.
Just drag your PiP Clip to the Timeline. Let it go where it wants, such as at the end of other Clips on Video Track 1. Then, drag it to Video Track 2, and place it where desired. Animate it, as is needed. Note: in my example, there are other elements stacked up, including a Title and a semi-Transparent graphic element. All can be animated with Keyframes on the various fixed Effects, like Motion>Position, Motion>Scale, Opacity, plus most added Effects.
* Remember, the trial version will add a watermark to the Exported/Shared output. This FAQ Entry will tell you how to remove that, when you buy the program.
Thank you all for help. i was able to get it working.
Great news, and thank you for reporting your success.