Can you tell me about the transformation of the mosque and Baba's connection to the festival of lights?

Certainly. Chapter 5 notes that a significant transformation of the mosque began in 1912. Before this, the ground had knee-deep holes, but through the devotees' efforts, the flooring was paved with stones in a single night. The same chapter highlights Baba's great fondness for the festival of lights. He would celebrate Diwali by tearing rags to make wicks and personally visiting grocers to ask for oil. It was during one of these times that the shopkeepers refused him, leading to the miracle where he used water instead of oil to light the lamps, which then burned throughout the night.