Unhappy [Q] Uh-Oh, TWRP not allowing me to mount via USB

$10 paypal to who can help me solve this

Here's the deal people,

My GNex was slowing down and acting all funny with stock 4.3 after about 6 months

I finally decided to try out a 4.4.2 ROM

I had TWRP on the phone so I said I'd just copy the Zip to the root folder along with the Gapps

Long story short, I accidentally wiped the storage.
Then I said no biggie, and figured that I'd just mount the USB to my laptop and transfer the Zip file of the ROM I wanted over to the storage.

BUT when ever I tap on mount USB nothing shows up in the devices.

Now I have nothing to transfer the files to.

I have windows 8 on the computer I'm currently using if that matters.

Forgive me people. I am not an avid flasher like I was when windows phone 6 was still around. So spare the insults . Just need my phone running so I can contact my loved ones