How can I make a stretching arm without stretching its hand

Hello,

I'm having some problems, and hope anyone can guide me through them, thank you in advance.

Problems I'm facing:

     1. The arm stretches just fine, but the hands go nuts, I know the arm is doing it, but since it's a simple shape we won't notice it. So how can I make it follow the arm, but in a way that it doesn't stretch along with it;

     2. The sleeves are stretching too. I just want the arm to stretch.

     3. The sleeves are in front of the arm. I can't figure a way out to make the forearm go in front of the sleeve but still be attached to the upper arm.

The scene goes like this:

     - Boy stretches its arm and grab the popcorn [ press C and V for popcorn and upside-down popcorn ]

     - Then he grabs some popcorn and eat it

     - End

I got Pickupbot as an example, but it has the same problem I'm trying to avoid.

Puppet file:

Dropbox - Animeese_CharacterAnimator.puppet

Cheerio.