Hi Alexandr, yes please post your 3DM model file with those curves in it so that I can examine the actual geometry.

It looks like possibly your profile curve may be kind of slanted instead of perpendicular to the rails or something like that? It's difficult to tell what is going on just looking at a screenshot though since I cannot rotate a screenshot or zoom in or things like that which I can do with a 3DM file, that's why it helps a lot to post the 3DM model file with your geometry in it.

- Michael