Bug 1 is quite serious, sometimes all gestures will stop working for no reason, and sometimes quitting some app (safari in my case) is the trigger of this bug. All gestures are gone, you can't go to mission control by doing 4-fingers-swipe-up or can't switch desktops by doing 3/4-fingers-swipe-left-right. And the tricky part is: these gestures aren't actually "failed", they are still there, you still can do them when your mouse cursor is at some specific location, like on dock. Yeah, it's bloody weird, if they works depend on where your cursor is. The second one has been existing for long time (since mavericks if I remember right), The two-finger-swipe gesture fails with no warning. sometimes you just browse the web and do this gesture to go back to previous pages or do it on mac app store to switch pages and it jammed. Yosemite seems fixed this from DP1, but on DP7 this bug came back.