The fact that you are talking about forest roads and use the phrase 'nothing crazy" tells me you don't need to worry about the CoG of your truck / camper. Given the weight difference between your truck and your camper you would have to be on a pretty extreme side slope to have any worries about it's CoG affecting your chance of rolling the vehicle over. Usually, unless someone is very experienced and confident driving offroad they will chicken out long before getting to the point where the vehicle will tip (the exception is if too much speed is involved). I.e. unless you are used to it the angle will feel much more extreme from inside the vehicle than it clearly is when outside.
I try to minimize storing weight high up in my camper not for fear of it tipping over offroad (and anyone who knows me knows I do take my camper off road), but because the momentum of all that weight acts like an inverted pendulum and will put stress on the camper body and tie-downs.
The latter is the thing you really need to consider - how you are locating and securing the camper. When driving offroad it gets thrown around and you need to have it securely located in the load bed or it will shift. I have fitted timber outriggers to widen the bottom of my camper so it exactly fits between the wheel arches and keep it pulled against the front bulkhead of the truck bed which works to prevent the camper shifting when negotiating the rough stuff.
Steve.