Re: recommend some biographies.
In Shahabnama, he indicated two incidents of his life, which I personally believe his closeness to Allah
As a deputy commissioner of Jhang, one time a *buzurg/*Old man came to him and asked for help and told him that Prophet Muhammad (saw) came into his dream and instructed him to ask help from Qudrat Ullah Shahab.
Before partition, he was working in Orissa Secretariat, and his housing was a ghost house. He wrote in his autobiography that every night he went through different experiences and events. One time when he was listening a song from gramophone, it started sounding differently. But when he put the piece of paper of first kalma. it sounded correctly. and then he repeated his experience with roman words of kalma. but gramophone only worked with arabic kalma.
other than that,
Dilon ka raaz to Allah hi janta hai, but I think Shahab saheb and his friends like Mumtaz Mufti exaggerated thing to a great extent. There is one thing fiction, which if crosses its boundaries become myth. I think many of the chapters in Shahbnama and Alakh Nagri crossed those limits