Your should have plenty of room each side of you, to fair we were asked by the guys guiding people in to rows if we were putting up an awning and which side we plan to put it up. People had plenty of room in the rows around us, we had a Vango awning attached to the side of our camper.
Some people had huge family tents next to motorhomes which did not seem to get in other peoples way, I think the only issue would be people blocking the fire lanes at the front and rear. if you need to start your engine I would do it in the day and be aware that the fumes are not going into your awing etc. We did not start our van up once from parking up Tuesday until the Sunday night when we had to leave for home.
One top tip peg down an breathable hessian ground sheet from your awning/gazebo to the entrance to your motorhome it will keep out mud dirt etc. if you use an waterproof ground sheet it will just collect water.
You will be fine, get set up and chill. Have a good one.