I've emailed the organiser and hope to enter the 161km on the line.
Does anyone know exactly where the start is? Shaftesbury CC website doesn't have an address, or I couldn't find it. Is it near the Comrades CC bungalow where the Essex Air Ambulance event was a few months ago?
Also, for anyone catching the train from London, there's engineering work happening tomorrow. National Rail Website shows train to Bishops Stortford, then bus to Elsenham. So, you'll have to ride from Bishops Stortford to the start. It's about 8 or 10 km, Google Maps tells me.
Cheers adamski for posting the .gpx and .tcx files. Now to work out what to do with them!