Thanks again for the clarification in the last post. Cleaning up the shape and reattaching it to a new editable spline fixed the problem for me. But unfortunately if a shape with more knots is necessary, the whole thing gets unstable again.
So I think an improvement in this area would really make sense. One last question about the slice function, would it be possible to add a feature to cap the sliced geometry? If it´s a boolean operation, that should be possible, right?
And I also have to say, overall I´m really happy with RailClone, it´s a great tool and made things so much easier for us. Thanks for that