Do I have to change my project to run on Linux and Mac?

I am currently making a game to run on PC. However, the topic came up and I am now considering deploying to Mac and Linux. Before I commit to that however, I wanted to know if there are major differences that I need to take into account when deploying for the other platforms? Are there code changes or network changes that I need to rework? Also, since I am using NGUI, I am not particularly worried about UI between platforms, but it is also a slight concern.

Thank you for your help.

There shouldn’t be much for changing, it should run just fine if you change it’s Build Settings in the Editor. As for the NGUI, it hopefully should run fine too.