I did my best to make the title as clear as possible but I'll explain in more detail.
I create tutorials for youtube and have a very standard setup.
In the top left corner I have a camera angle of my face+chest that I use for the presentation part of the tutorial (people like to see a face). And normally I would scale that video down manually in FCPX, add image mask, drag it to the top left corner and use ripple callouts to give it a nice frame. Has always worked but as I do this everytime I wanted to make a template for it so i did in motion.
I made an effect and it does the following things:
1. scales the video to the correct proportions
2. places it in the top left corner of the screen
3. creates a nice frame around the image
The trouble is that once the video is rendered in FCPX that specific camera angle looks almost like its a rendered proxy while the rest of the video and camera angles look razor sharp.