There is an installation script of sorts available for ubuntu 12.04.1 LTS. It may work with newer versions of Ubuntu, or other Ubuntu-like flavours of Linux. To install the game, run install.sh and follow the prompts. This download includes the source code, so in the event that the installer fails the game can still be compiled by hand.
The editor has been disabled for Linux due to the copy/paste feature not working.
Step 1: Extract the files.
Step 2: Mark the "install.sh" script as executable.
Step 3: Double-click the script to run it. Select 'run in terminal.
Step 4: Follow the installation instructions. (This may take on the order of 'an hour' for older computers.)
Now you can run the game whenever you want! Just double-click the file called "game" that has been created. Have fun!