I know you are rushed, but I have found, if it worked before my problem is usually going to be something simple, something I over looked. (did I turn the computer on <fp.) Take a deep breath and look at it again.
These are the steps I would try
It looks like Vixen thinks the dongle is on com port 8, but windows has assigned it a different com port.
Go into windows device manager and see what com port your dongle is actually using and set Vixen to use the same one.
Then reboot your computer so that everything that maybe using it is released.
Then when you plug the dongle in you should hear the windows beep. (make sure your USB cable is plugged in tightly on both sides)
Then open vixen and see if it is working.
If not is it a V2 dongle and do you get the lights?
are you using a profile for your sequences?
-Jeff