@jwatte I have now followed your tip and created a very simple mesh with a simple collision box. But somehow the error still occurs depending on how far the spline is away from other static meshes with collision on them. These is my testfile:
SplineTest.rar (97.7 KB)
Is this maybe a bug in 5.3? Is it important for the construction script at which position of the graph i enable the collision for the spline?