Hi Gunter, yes it should normally be base line first and curvy thing second. But the other way may produce a fairly similar effect since mapping from a curved base onto a line will also produce a certain kind of bending effect as well.

In v2.52 to get this type of curve flow to work it was needed to put both curves to be planar in the top view, if you rotate your objects so that it is like that, then it should probably work for you.

But I'd really recommend upgrading to v3 instead, there are a whole lot of improvements in v3 and one of them is to this specific issue that you're running into.

- Michael