1. After download those, for Zawgyi Tai font, just press it and add the font book like this kha and that's it ! :)
2. for Myanmar Zawgyi, we have to double click on the Zawgyi-KB.dmg File and it will appear like this:
After that, just Press the Zawgy.Keyloayout and Zawgyi.icns to Keyboard Layouts one by one. Then Press the Zawgyi One.ttf to fonts like the Arrow kha...