Install some dependencies:
apt-get install build-essential librsvg2-dev libcairo2-dev \
libfreetype6-dev yasm libjpeg62-turbo-dev swig 

Be sure FFmpeg is installed, preferably from source.

Install rvm; rvm install 1.9.2; rvm --default use 1.9.2
gem install --pre patchbay
gem install thin
gem install trollop

Install v8 - compile from the source: 
https://code.google.com/p/v8-wiki/wiki/BuildingWithGYP 
and build as a shared library

Install libjpeg_turbo! libjpeg62-dev on Debian jessie is libjpeg-turbo as of 12/2/2015.

Quick start guide to make up for very incomplete documentation:
make replay/replay.so input/input.so
cd replay

mv replay_config.rb.example replay_config.rb
vim replay_config.rb	# set up your sources

vim replay_server.rb	# search for create_decklink_output_adapter, change 7
			# to the card number you want to use for output

ruby replay_server.rb	# make sure your ShuttlePRO controller is plugged in;
			# also make sure your console is at 1920x1080