I Can answer few of them
1Q relation between preheater fan power variation with prehaeter draft increase/decrease?
1 Ans: Power is proportional to diffrence in static pressure, Hence power increases with preheater draft increase and vice versa.
5Q:what is the relation with preheater exit temperature with feed rate?
5 Ans: As we increase kiln feed rate, intensity of gas temperature lessens hence density of gases increases consequently preheater fan power increases and vice versa.
3Q what is the relation with feed with preheater fan flow?
3Ans: As feed to kiln is increased it adds more and more resistance to the flow consequently increasing pressure drop hence power decreases and flow decreases.
I Hope i am right. and i think that your 2 , 3 and 4th question are more are less the same.