I'm currently running the 7.0 and as far as I know this is the latest update. When I try to search for an update it says that I am running the latest one. Maybe it was a mistake that they released the 7.1.1 version? Maybe only you got it? Who knows. I guess that you have to re-flash the latest 7.0 one.
The fingerpint unlock doesn't need more than 0.3s to be processed but the screen wake-up needs a longer time. You can try to wake up your phone first with the power button, then use the fingerprint sensor. Later updates might make the screen wake-up faster.