With no intermediate points, the trail is jagged and sharp, but renders fine:

If I change the intermediate points the lines become smoother (which is what I want) but the render is wrong, and then Cinema crashes:

Hope this isn't too tricky to fix! Scene file here:
https://www.dropbox.com/s/gsd029e11q0u0 ... r.zip?dl=1
Windows 10, 128Gb RAM, NVidia 3080.