Official comment
These don't really seem to be related to the 14.2 update.
1. This is not the case but there is something weird going on there. It does default to being Metric. If you switch the value to not be metric in the Settings then the units are not displayed in Metric. The button to switch the unit type seems to not get set properly at first when the units are not set to Metric in the Settings.
2. That button doesn't do anything to contact the aircraft. It changes the area the map displays to follow the user, follow the drone or show the whole area of the survey. If that camera flipped up that was likely a coincidence or you possibly have your C1 and C2 buttons set to move the camera (which is common).
3. Yes, this reading is not accurate if the aircraft is slowed due to lighting conditions. This estimate is made while the aircraft is on the ground and assumes that the programmed flight speed will be executed.
4. Correct. It does nothing during mission planning. It changes the way the aircraft turns to combat gimbal drift issues on certain aircraft. Straight corners goes further into the corner, turns, and continues. Curved corners are the default way and keep the aircraft moving. Curved flights take a little less time. The flight time estimates do not take the Straight mode setting into account.
5. 5.0