I have been putting lower thirds on my video without any trouble. My lower thirds have been jpeg images. I simple drag them onto the timeline and they lay right over my main video.
My trouble now is, I've just obtained an animated lower third that is not a picture file, but a movie file. When I lay it on the time line it doesn't lay on top of my main video, but rather blanks it out.
I tried the video merge option, but it leaves some moving black pixels around the lower third image.
How can I lay one video (my lower third video image) over my main video?
Sounds like the video doesn't have a transparent background.
What format is the file? It should be Uncompressed AVI to work well in Premiere Elements.
The video needs to have preserved the transparent Alpha channel.
We have many of these types of lower thirds and motion backgrounds at muvipix.com and I have created many of them myself.
Depending on what format the file is will tell us something that may help.
If you cannot get an Alpha Channel for this Lower-Third, you should be able to do one of several other things:
1.) use the Garbage Matte
2.) use the Crop Effect
3.) use Track Matte Keying and create, basically a new Alpha Channel
Or you may be able to use the Chroma Key to key out the background if it is all one solid color.