2.You said no problem here...

3.After 1st or 2nd period:
After 2nd period
Leading by... 3 to 99 Change to low
'otherwise Normal' <-- can be set only if you are trailing (0 to 99) or if after first period you weren't leading by 4.
I can't see any possibility to set Normal if you are leading with 1 to 3 goals and you have 'Leading by... 3 to 99 Change to low ' condition enabled.