Hey there, you should just have to unzip the file. :)
I've unzipped the file, but I'm afraid that it's not at all obvious what to do to actually play :-)
Edit: okay, found "FruitsOfaFeather.x86". I was confused by the fact that my unzipper didn't create a new directory for the entire contents, so I ended up in the FruitsOfAFeather_Data directory. That being said, I'm still not able to play the game. A little googling seems to suggest that the problem may be that I'm trying to run an x86 binary on a 64-bit machine..
There seems to be a lot of mono dll's and unity-stuff, but there's no executable file that I can find.