Attempting to attach a Static Mesh Component to a modified Spline Mesh Component procedurally fails
Static Meshes can only be attached to procedurally unmodified Mesh Components
Add it in the structure first, and then modify it later.
PIE: Warning: Attached to: "/Game/StarterContent/Maps/UEDPIE_0_Minimal_Default.Minimal_Default:PersistentLevel.AC_ODLine_C_0.Spline" is not static (in blueprint "AC_ODLine"), cannot attach static "/Game/StarterContent/Maps/UEDPIE_0_Minimal_Default .Minimal_Default:PersistentLevel.AC_ODLine_C_0.NODE_AddSplineMeshComponent-3_0". Aborting.