I use Anquet Maps for route planning and for generating GPS co-ordinates. Although Anquet is now available for Mac, it isn't fully functional - so I use Anquet running on Windows XP on a MacBook.
An interesting feature of Anquet, is that you can do a 3D flythrough of the route. This shows the entire 10-12 hour challenge compressed into a few minutes. The map used is a Harvey Superscale which I think is better than the regular OS map of the area. These maps are specifically made for hikers.
The route is based on that recommended by go4awalk.com (walk 101). The screencast was done using Camtasia Studio 7 which is a very good tool for screen recording and making how-to videos etc, much better than iShowU I think but I prefer not to use Windows where possible.
Links
http://www.anquet.co.uk/?gclid=CPKuye7DraMCFQY9lAodEEWS6Q
http://www.techsmith.com/camtasia.asp
