So, I bought and downloaded the game and then got "Application Can't Be Loaded" with OS X, but it was easily solved.
In case someone else has the same problem with the game before a fix surfaces, this terminal command helped:
chmod 755 skyrogue.app/Contents/MacOS/skyrogue
Then you just have to do the usual -> CTRL + Click and then Open.
I found the solution in Unity Answers: http://answers.unity3d.com/questions/802960/using-...