I'm working with adobe encore CS3 and I would like to know if it is possible to make a video as an highlight or an animated gif also as an highlight. If it's not, could you tell me witch software can do it?
I don't think this is possible. What you could do is have a button activate automatically when selected, sending the end user to a new menu which is a replica of the first except that the new menu includes the motion effect you want.
If you want to learn more about how subpictures (the official name for highlights) work, just search for that word rather than highlights. You might come up with something.