Can someone explain me what is the role and meaning of "ever" in this sentence? "Before the present author ever became associated with ..."
It is simply used for emphasis. The meaning is the same.
The reason that it can be used for emphasis is that it is difficult to find a word to emphasise in the expression, " "Before the present author became associated with ...". It would be possible to emphasise "became" but "became" isn't a strong word. By introducing "ever", we can place a strong vocal emphasis on the word "ever".