Does TPMS use the reset figure as correct?

When you have inflated your car tyres and re-set the monitoring system inside the car does those "new" tyre pressures become the norm? If the pressure drops from the "reset tyre pressures (the norm)" by...

Do I need to drive my car set the tyre pressure monitoring system?

After I have adjusted all four tyres to manufactures recommended settings and reset the onboard system, a message appears saying 'tyre pressure registered.' Should I at this point drive the car to set...

Does it matter if one of my tyres has a different load rating?

Due to having had a puncture we now have a 95V rating tyre whereas all the remaining three original tyres are 91V. Is this illegal or dangerous? The supplying dealer says this is causing tyre pressure...