tarzanman - a little thing a found which helped me out on that is... well first off you need to toolbox for NL (
www.gravimetricstudios.com) Then open up your uncompleted track with the toolbox. Then there should be a tabbed named rotate, and thats exactly what you do, you rotate the track so the section you are about the create would line up straight on the grid. Onced youve completed that piece of track you can move the track back round