Quote - That's one of them.  On first reading I didn't think that would work for this set as the track doesn't follow simple arcs, it curves around the terrain following the path the real one takes.

One solution is to cheat a little on the curve shape so that it's a mathematically simpler form, or you'll need to work with splines some how.

One way would be to insert marker objects (that can be made invisible), that are named in sequence and then use a script to generate keyframes for position and rotation based on spline evaluated at the item positions.
Another possibility is to see if you can use a Walk Path for at least some of the work (see some of lesbentley's posts (e.g. -> http://www.renderosity.com/mod/forumpro/showthread.php?thread_id=2318233)

And a question, is this Glenfinnan your recreating (or a particular scene based on one of the HP movies) ?