I mostly play on Windows PC and PS4. Started playing on my Mac Client running on:

OSX Yosemite - Version 10.10.3
MacBook Pro (Retina, Mid 2012)
Processor: 2.7 GHz Intel Core i7
Memory: 16 GB 1600 MHz DDR3
Video Card: NVIDIA GeForce GT 650M 1024 MB

Steps:
1. Zone into different areas of the game
2. Repeat

Result:
The entire UI blinks on and off repeatedly and requires client restart or crashes.

NOTES:
So far the Mac client appears to be very unstable on my Macbook Pro. Lots of blinking UI issues after zoning into areas and very low FPS for this kind of system specs. Graphical corruption sometimes occurs as well between switching areas. A lot of the symptoms remind me of the similar emulation issues seen when trying to play FFXIV using Wine emulation software. I know a third party, not SE, worked on the Mac client, but I don't know if they can be contacted and left with any bugs.