Hi lyes, currently a simple solution for that is to hide the other objects that are interfering with your point picking.

If you only have that arc visible, it should then be easy to tell which center point will belong to it since there will be only one.

But there are probably a couple of different things I can do in the future to improve this situation - having the center point show up as a grip when it is selected as we were previously discussing is one thing that would probably help since it would give you a way to identify it, and maybe showing some kind of highlight on the curve that has a center osnap active on it would also help.

But again, I'm not sure exactly when I will be able to do those, for now just hide the other things and that should let you complete that task pretty easily in the current version.

- Michael