While my account differs from Tims it pretty much reflects the difference between our relative experience on trails....My major problem was caused by a pair of Nike Triax GTX "trail" shoes I had just bought. I use the road version of these trainers as wear orthotics and after years of trial and error finally settled on these......Problem is the trail shoe version are errrrrrrrr not actually trail shoes as such....Certainly a bit more rugged than the road shoes but certainly not adequate for this run......So as a newbie to trails (and somebody who has now been out injured for 4 weeks having twisted a cartlidge in my knee on the beck section) these are my tips and wish list for this race.
1. Pray the temps on the moor are VERY cold. The mud was an absolute nightmare. When we were there it was mild and wet and it created a lot of issues...Would be great if the moor area was frozen 
2. Trail shoes are a must. I suspect my injury occured because of me unwittingly having inadequate footwear.
3. I originally had a plan to run 20 mins, walk 5 mins......My plan now is to walk the more difficult and technical sections such as the beck and long moor stretch....There are some really fast areas on this race and it seems madness to be walking any of those then trying to run a section where the running is so technical, treacherous and energy sapping.
4. The wind/waterproofs are non optional, wind not a huge issue until you get onto the moor but once you are up there it is pretty brutal even on a nice day.
Despite the injury we ran 32 miles that day and having never run trails I have to say this course has me converted to trails.....It is hard, stunning and brutal and I am praying that i can get back to running in the next 10 days so that I have some chance of making race day 