I can't tell you what will instantly make you feel better, but try your luck with the following:
Set your suspension to the "sport" setting. It's much harder, but if that doent help, try leaving the rear as sport and soften the front rebound and dampening to normal or comfort. The idea is to track better into the sand or surfaces while providing you a solid platform with which to accelerate and put power down.
I also feel comfortable running the Continental TKC 80 Twinduro tire at ~ 38 psi rear and 32 front. I personally would not go lower than 25 front and rear, but try playing with those settings. Nothing bad will happen at 25, you'll just experience greatly increased tire wear.
Lastly, try not to get intimidated by the weight. The bike is indeed very nimble if you're not scared. Try to find a neutral throttle, or slighly on the gas. The rear of the bike should iether slide, or feel very light and glide through the turn.
I will email a copy of this to you as well. Good luck and let us know what helps and what doesnt!