This is the part, where I end up writing, copying, hacking code to get things to work.

My usual route in a project like this with many different components is to first try each and every thing separately with separate code, libraries and such - as usually there are examples available online for almost everything these days - especially many many THANKS to Adafruit.

So, I made a GitHub repo to record my work for the code part - this was being done on the VeroBoard prototype while the PCBs were on their way - these LOGS are not in order - https://github.com/zaidpirwani/PiMon

The prototype setup is shown

In the end, I had it in such a way that one of the Push Buttons would make the Pi Shutdown in a clean manner, the LCD would show current date and time and the IP of the network. The LCD also showed Temperature and Humidity values coming in from the DHT11 Sensor and the DS18b20 Sensor.

I also had the LED blink once every second to show that the system was indeed working.

Still to do is the IR Sensor.