Question 2
This is a recognised fault condition with the aircraft.
"Several operators have reported seeing the temperature indicator move when master caution is recalled, while the annunciator switch is being pressed. One operator has also reported the temperature indicator moving to zero when either air conditioning pack switch is placed in the HIGH position."
"During troubleshooting it was determined that high resistance between ground block GD506 and airplane structure can cause temperature indication to vary under certain conditions. There are several different ground types installed in GD506 which, when the resistance to ground is too high, will affect temperature indication."
"Operators who experience movement of the temperature indicator when master caution is recalled or during any other operation may wish to measure the resistance between ground block GD506 and airplane structure. If the measured resistance is above 0.0035, Boeing recommends operators correct the condition."