So we built it using the Unity Exporter for Linux/Max/Windows. Theoretically it should work for them but we don't have the ability to test it due to not having a Mac or Linux Machine. We had someone play an earlier build just fine on Linux so I assumed it was still working. I will see if I can get them to play it.
Noted on the Fullscreen button. I think there used to be one but it broke. Thanks for the suggestion!