I used the split method and was able to isolate the clip so that the effect only applied to it. However, I still ran into the same problem with the effect starting at the beginning of the source clip. Like if you double-click the clip, it shows the entire source video in the display and I can see the effect happening right at the beginning. Usually with basic effects I’d be able to fix this with a couple keyframes, but the shatter effect is pretty convoluted and doesn’t really have a way to set when the shatter occurs.