From your picture is looks as though the corner is defined by a number of vertices and each of these is generating a corner segment. In RailClone you can define what types of vertex generate a corner segment using the Vertex Type
If the style is currently creating a segment on Corner or Corner-Bezier vertices you could change the base spline so that it doesn't use either of these types. Alternatively you can use this dropdown to change the vertex types that generate a corner segment. For Example Change this to Corner to stop it adding segments on Bezier-Corner vertices.
I hope that helps, please let me know if you have any further questions.