Latency problem with my uefn island

[Hardcawcanary]

Just seen this post

Best Practices for Decorative Cinematics

I have an island nearing completion and it seemed to be running very smoothly, but then as a final decorative touch I added a cinematic where one mesh was moved through the sky with four attached static meshes, all pretty low-poly --No luck, lag-city. Having one five-minute looping cinematic with only two keys (one at the beginning and one at the end, started making things lag and jump. I made the simple static meshes “no collision” and obviously “moveable”. Am I missing any other optimization…