You'll have a great time! As a relative newbie, here's a few tips that might be of some help.
Basically the scoring works on a 1, 2, 3, 5 basis. Each touch of the foot is 1, up to a total of three. Once you get 3, you can virtually paddle your way through. 5 is a failure (see; crash, stall, backwards motion, etc). Under the new FIM rules (same as AMA, far as I know) you are permitted to stop without penalty, so if you have to put a foot down, you don't need to rush it. just keep the foot planted and stop till you are ready to continue.
Remember that when dabbing (putting foot down) you cannot drag or skid your foot (or you get more points). So when taking a dab, do it with some consideration for where you put your foot for maximum benefit ;) (ie; to allow you to better turn the bike around a tight turn).
Walk the sections carefully and try to memorize each obstacle. You don't want any surprises. If you can visualize running through the section, remembering each rock, turn, root, etc.
One of the biggest things is to simple take your time. Don't worry about racing through the section, you will not run out of time (don't worry about the timer). Watch the riders before you and see where they are having problems, so that you can be prepared. Try to hook up with a couple of the "good" riders in your class, to get tips and see how they negotiate the sections.
It would be wise to try to zip around a little on the bike before the start, just to get familiar with the feel of it, throttle, clutch, steering and such. As you know they are quite different feeling than your KTM ;)
You'll have a blast! Just take your time, relax and have fun with it. :thumb: