MAC Yosemite, LR 5.7 & 5.6, when I use trackpad gesture to pinch in or out (zoom in or zoom out) in the grid module, all of my photos change their aspect ratio (they become squeezed in or out) also the grid moves to the left of right and some of the photos are not visible, I have to scroll left or right - this never occured before LR 5.5 or earlier.