Follow these steps to enable resizing of the game window;

Open up Windows Explorer and go to:
<YOUR STEAM LOCATION>\SteamApps\common\TripleTown\META-INF\AIR\

If you cant find the location you can go to your steam library. Right click on Triple Town and select "Properties", then click on the tab called "Local Files", and finally select "Browse Local Files".

Theres a file called; "application.xml"
Right click it and select "edit".

Search for the following line:
<resizable>false</resizable>

And edit it to:
<resizable>true</resizable>

Now, when you start the game, you can resize the game window at your will.
Just grab any side of the screen and drag it to the position where you want it to be .

Note that,

• If you resize both the vertical and horizontal size, it will stretch the game.
  
• If you only resize one, for example the horizontal size, then it will add more world arround the playfield. Making this also enjoyable on multi monitor set ups where the player island is across the complete screen.
  
• The main game will be positioned at the left part of the screen when only enlarging horizontally.