i currently use the standalone wallet 2.6.4
i am wanting to upgrade to 2.7.11, do i just down load a new standalone? does it referance the already created wallet.dat in Appdata or does it create its own?
Yes, just download and open the new standalone executable. It'll open and upgrade your old wallet. Make sure you save the seed beforehand (it should be safe but just in case).
Note that the upgraded old wallet can't be opened using electrum versions older than 2.7.x.