hey man, pretty new here, but hell I thought I would give replying to this a shot... if anyone wants to correct what I am saying please go ahead, I am here to learn like everybody else.
The problem you are having starts with the way that encypted wireless traffic works... first off you have two parties, they start an encrypted session by sharing with one another their "key", but hell, lets just make this simple... lets say name... son.. and dad..
Now, son and dad trust one another.. and they are able to share a secret code that mom doesnt understand. so everytime son wants to talk to dad... he says "hey dad, this is son... is that you?" and dad says " his son, this is dad".... thereafter they can talk without mum knowing what they are saying.
If the response was to be mom... or sister... or stranger on the street... obviously son wouldnt say anything.
This is the VERY simplified reason that you cant kick someone off an encrypted wireless connection and get them to talk to yours instead...
THE RABBIT HOLE GOES DEEPER...
So... why cant we just call ourself dad? seems simple right?? well... in addition to dad saying he is dad... and son saying he is son... there is a secret that they both share... a secret word.. this secret word is, of course encrypted... but... it is possible to "sniff" the encrypted password and work out what it is by comparing a "dictionary" with its encrypted version of the word... its going to take time, and brainpower, but it is possible.
Thats pretty much the long and short of it... you have a starting point now, and hopefully an understanding of how it works... is it impossible using your tetra to penitrate WPA2 networks... absolutely not. But its a hell of a lot easier to intercept traffic on unencrypted (open) networks at $randomwifihotspot.
The reason nobody replied is because in the short time I have been here, I have seen this question pop up a LOT. and it basically comes down to handing someone with no experience a potentially devistating tool, end epowering them to learn why its not working.