I do not think there is any off roading adjacent to the campground, but there are areas nearby.

I have a SxS and a Jeep, but we only hiked. While hiking and driving around the area we did not see OHV "trails", but you can probably find very tame fire roads etc. like we've done out west. Sorry I couldn't be more help.

No I don't believe there is any off-road trails that you can use sorry I don't have more information

No, but you can find some if you drive around to the NE part of the range, near the Peppersauce CG.