After reading over the overall script of the movie, I decided I wanted to add another scene and animation to the overall plot, so I had to go back to insert those elements into the overall film. But the film already has 8000 individual keyframes and many different layers. So the only way I can think of inserting them is to select all layers and to cut and paste them into later time in the time line (for example, if I have layers A, B, C from keyframes 1 - 8000 and I wanted to insert layers D, E, F into 4000 - 5000, then I would cut A, B, C from 4000 - 8000 and paste it into 5000 - 9000). Is this the only way to do it, or are there an alternative (preferably easier and “cleaner” way to do this)?
It will most likely be what you’ll end up doing.
From the information you have given, I read that you have a single Harmony scene which, in fact, contains all of your movie scenes.
This is not necessarily something we recommend, as your single Harmony scene could become heavy and it can be more confusing to make changes, since having so many assets can be hard to organize. The standard workflow would consist in creating a new Harmony scene for every single animation scene in your movie.
I hope this helps,