I have a Mac Pro desktop with a pretty good graphics card. When I first started using the new client I got freezing, frozen up to 45 seconds or longer, while the shaders were built. after 4 or 5 minutes after I had turned a bit and moved a bit most of the freezing was done with, at least until I went on a different map with a different style for the first time and then I would get some minor lagging. If the game freezes just be patient and wait and see if it unfreezes. If it does then it is probably the shaders being calculated. Just stay with int and in 5 to 10 minutes you should be done with the freezing issue.