I made SK3 off the September '07 exam. I will be taking the SK2 exam this September (right?). I transferred from my first command in December '07. Shortly after I checked into my new Command I was injured in a motorcycle accident and received an NOB transfer eval. I was at TPU for a couple months and transfered to my LIMDU command where I will also be receiving an NOB. Do NOB's affect my chance of advancement or will they look at my last periodic evals which were EP's from when I was an e-3? Will I even be able to take the test because of this? An NOB would probably hurt my chance of advancement.

You need an E4 eval to take the E5 exam, can't be NOB. Also, your transfer eval should have come from your last command, not your new command.