Japan visa application form – what to fill for “Issuing Authority” on Indian passport?

Hi, I am applying for a Japan tourist visa through VFS Chennai and had a couple of doubts while filling the visa application form.

My Indian passport shows “Place of Issue: Chennai”, but I don’t see any separate “Issuing Authority” mentioned on the passport.
For the Issuing Authority field in the Japan visa application, what did you guys enter? Did you put Government of India / Regional Passport Office Chennai, or leave it blank?
Also, for fields that are not applicable, such as:
Former/other nationality
Other names
Previous stays in Japan
Certificate of Eligibility number
Guarantor/reference in Japan
Inviter in Japan
Partner’s profession (I am single)
Remarks/special circumstances
Did you enter “N/A” / “None”, or simply leave them blank?

Also once i get the visa, i can change my travel dates accordingly within the visa approved time which is 3 months.? Shouldnt be an issue that it should match with my original mentioned dates when i applied for visa?