Share transfer and demat

1. I have shares in physical form and in joint names. Now I want to convert the shares into my name and also in demat form

2. I have filled in details in Form SH 4. I have doubts with regard to Form SH 4

a) In the place of witness, can witness be any person or it should be gazette officer

b) Stamp duty to be paid. In whose name stamp has to be purchased. What should be printed on stamp paper.

c) What should be filled in the box referred as Stamps in Form SH 4

d) What are the enclosures I need to submit in case of signature mismatch