The pest control is very good...you wont need an awning.
Maybe a squirt or two of OFF around your ankles in the evening if skeeters are highly attracted to you....but its nothing like REAL FLORIDA at the fort.
You won't need the screen room I do take a fan or 2 for under the awning. The fans will keep you cool and if there any bugs they'll keep them off of you.
Been to the fort many times. spring summer fall winter and have never had a problem with mosquitos. Deer flies sometimes in the spring around Mem Day. You might have more rain than bugs. They do a great job of bug control.
Hope this helps some and have a great time at the fort
Go to walmart and get a therma cell mosquito repeller (don't know if that is even a word ) in the camping section. It gives you a 15ft dia. and ACTUALLY WORKS!
It only gives you like 8 hour or so on each pad so you would only want to use it when you are outside sitting. But I can actually say it works.
OK, I must be the only one who tastes good to mosquitos. Every time I go to the campfire, I get all bit up. It doesn't happen anywhere else at Disney or at any other time of day. It kind of spoils the movie for me...