I felt your initial instructions were quite clear. However, I'm experienced with MyDMX, and clearly the original poster is not that experienced yet.
The original poster's concern and problem is that they want to basically overlay one set of movement from one set of fixtures with a pre-existing scene that has other movement with other fixtures. Sort of a "scene merge". You and I came to the same conclusion that this is not going to be a quick fix as it will involve pen, paper and manually adjusting things.
My only super complicated scene came from a recent show I still work with. Even so, it was not that complicated. I have movement in a scene, and the director wants to set one side of wash from 100% to 50%, and the other side needs to wash from 0% to 100% while the movement was still going on. Since the wash changes took place at the same time, that in and of itself would be no big deal, but I had movement going on with 2 moving yoke fixtures. I had to manually adjust 4 wash fixtures from 100% to 50%, then come back, start over and set the other 4 from 0-100%.
In my case, this was fairly simple. Then I found out I had a new problem: The movement was on the WRONG SIDE!!(one light moved, the other was idle, and I flip flopped them by accident). So, now I had to go replicate the movement to the other fixture. Now, instead of killing the other fixture, I just closed the shutter, JUSt in case it was wanted again!
Lesson learned: DOUBLE CHECK the director's notes!!