NQ - Tricky one, after a road marathon I tend to do too much, too soon, but two weeks sounds fine to me. Your body would be or will during the event tell you how recovered you are. Maybe boost the carb meal the night before more than usual to give you some confidence in your energy stores.
Re. nav talk. I always carry a compass, but don't think I've ever used it. Many events provide adequate "destructions" and if not a well marked map will see you right. Especially if you learn what the differant track/path/road types are, read the contours, look for sightings - e.g. things like distant settlements, rivers, even pylons are great for this in all but the wildest English countryside - and orientate it with your actual direction as you move. Also worth carrying a GPS as backup (garmin forerunners nav funcs will do for events under about 8-15 hours - mode depending), if you know how to upload grid refs (freeware on t'net for this) or track/routes. Check out grough route, a must for the outdoor entusiast wanting to map event routes or plan own adventures. I'm sure a compass is a must in barren wilderness or desert environments, but how many of them do we really have in uk? Your never far from a/b-road or other navigatable feature, even if there isn't another human for miles around.
XC for me tomorrow, 6m off-road sounds easy but these things are a heck of a pace its more like a 10k road race. I've already planned my tactic to avoid getting stuck in a queue for first gate about a half a mile in without risking blow-up. I figure those who've given it thought will run hard up first hill, I'll leave them to that and make good strides down the hill following that (I hope). Excited... first race, or even event since early August 
Edited: 13/11/2010 at 11:54