The brush cursor is not working on my retina iMac and Yosemite OSX in Photoshop CC. I saw someone else in the forums had this issue and followed Adobe's advice to reset the preferences (Photoshop: Brush cursor bug on retina iMac running OSX 10.10 Yosemite). I tried both ways resetting preferences as described by Julieanne Kost in her video. Unfortunately, even though the preferences reset, this did not fix the bug. The brush cursor still stops at 50. The outline of the brush disappears after 50 and any larger brushes just show either a hand, arrow, or crosshair, which makes it impossible to edit my photos. I tried resetting twice and this problem still persists. What should I try next?
If 10.10.1 doesn't fix it, then you need to llet Apple know about this issue so they can get more information they need to solve the video driver bug.
Also, which specific model iMac and GPU are you using (so we can try to keep track of which driver is broken)?
I have the same problem, but interestingly, only on one login! Photoshop works fine on one login on the iMac and has the problem described above on the other login, despite zapping the prefs (and experimentally copying over the working set).
Spec is iMac Retina 5K 27 inch late 2014, 4Ghz Intel Core i7, 16Mb RAM and an AMD Radeon R9 M295X 4096Mb.