My answer by points
Did you check you "device manager" on your computer to see if it is even showing the device either as an unknown or maybe an error
YES is showing under USB as Unknown Device.
https://www.dropbox.com/s/nqbchoxg9u7e7mb/Screenshot 2014-05-14 15.47.56.png
Are you running Windows 7?
YES I am running W7
Just to be clear, when you try holding volume down + power then when it turns on release the power button while still holding volume down until recovery screen comes up all you get is "Downloading...etc .."
YES
As far as plugging the device in while in odin mode after pressing volume up to continue and plugging into computer you said you get an error on your computer correct?
YES the USB s not recognize
Just trying to gather all the info I can to see if you can fix it.
If its a driver issue or not recognized it might be due to the MTP which would lead you here for a solution.
IS a tablet GT N8013
What has happened at this point is you tried flashing a custom ROM on an un-rooted device with a stock recovery. Now at this point your phone doesn't likely have any of the original software in it to allow you to boot let alone even do a a recovery from stock recovery. Your lucky the device even powers on first off because if it was a hard hard brick the device wouldn't boot, charge, or flicker the screen regardless of button combinations and would need jtagd. Now even if you could return it they most likely wont because of the custom binary count at a 6.