Yes, that helps, and you do understand the problem! Thanks much.
The plot has ‘thickened’ somewhat. I was following the proper procedure, but have discovered it was the particular effect that is giving me trouble.
I used the Browse Presets function you mentioned, which is where I found the effect I was interested in. It’s in the ‘Lights & Optical’ folder, and it’s called ‘Emerge’. This is the effect I attempted to use from the beginning. When I finally decided to try others, such as some of the animate in options, they all worked fine.
But that particular one, as well as others I’ve discovered since, won’t work for me. Could it be some sort of special mask setting or something? Could there extra steps necessary?
PS: I’m working with AE 7.0
Thanks again for the input. I’m very much a novice, so I appreciate all the help I can get!