[WOTLK] Mac El Capitan 10.11.3 - Resolution changing issue

Hi,

I've downloaded the Wotlk client from Warmanes download section, installed it and it runs perfectly. There is an issue though and I'd like to ask if someone else has this as well.

Everytime I open the client the resolution is changed and it looks like this http://postimg.org/image/yb9y0bl8d/
It doensn't matter if it's full screen or windowed mode, it still does it. I can change it in-game to normal and it works well up until I exit game and reopen it again. Please help if anyone had the problem and solved it!

Thanks