This "HowTo" assumes you're running a modern version of the Ubuntu Linux distribution. Ubuntu has a low barrier to entry and provides a rock-solid development environment.
Get the AVR compiler toolchain. Note that the version included in most distributions' repositories is out of date and does not support Atmel's latest XMEGA parts.
sudo apt-get remove binutils-avr gcc-avr avr-libc
sudo add-apt-repository ppa:nonolith/avr-toolchain
sudo apt-get update
sudo apt-get install atmel-toolchain-binutils-avr atmel-toolchain-gcc-avr atmel-toolchain-avr-libc
The PPA through which these tools are available is maintained by Nonolith Labs: http://www.nonolithlabs.com
Get the code.
git clone --recursive git://github.com/TakkTile/TakkTile-usb.git
Install the PyUSB-1.0 Python module.
cd TakkTile-usb/PyUSB; sudo python setup.py install
With an AVRISP-mkII programmer attached to the XMEGA on the board, install the bootloader and upload the firmware.
cd usb
git checkout master
cd bootloader
sudo make program
cd ../
git checkout pipe_refactor
cd ../
make update
To get a single set of calibrated, compensated samples from the first row of the board, simply run
sudo python TakkTile.py