Haneda - International to domestic transit

Hello everybody,
I bought a flight ticket from Naples to Kumamoto with Lufthansa/ANA .
My itinerary is:

Nap 18:05 Muc 19:45 Flight LH 1929
Muc 21:25 Tyo (HND) 15:50 +1 Flight NH 218
Tyo (HND) 17:55 +1 Kum 19:40 +1 Flight NH 647


It's the first time that I will take a domestic flight in Japan.
My questions are as follows:

1) At Haneda I'll have to pass immigration or this procedure will be performed in Kumamoto?

2) I'll have to pick up my luggage at Haneda or will be automatically shipped to Kumamoto?

3) The time available to me is enough?

4) As I should also withdraw the Japan Rail Pass, I can go to the JR East Travel Service and then come back to take the bus of the ANA? (The map is not very clear of where it is located)

Thank you so much!

All immigration and customs (luggage check) procedures will be done at your point of entry, Haneda International. Are you going by the same airline on both flights or at least on the same ticket? Then if your flight is late, you'll be covered by the airline, though I don't see a problem as immigration procedures in Japan are usually quite quick. A short train trip to the domestic terminal, with your luggage, will be all that is needed to go to your second flight.

I am not sure about your JR Pass issues.

Use the transit facilities as described here, this will save you time since you won't need to go through the "big" lines with everyone else. http://www.ana.co.jp/wws/japan/e/asw_common/departure/airport/map.html...

Unless you plan to use your JR Pass on the day of arrival (or early the next morning), exchange it at Kumamoto station. Exchanging it at Haneda would require going through the "big" immigration and customs line, so you can go to the exchange office which is in the "public" area.

Actually the transit facilities are only for the security check for the domestic flight and transportation between the terminals, so you go through the same immigration and customs line as everybody else. This means you will first end up in the arrival lobby of the international terminal, so depending on how much time you have left and how long the line at the JR Pass office is, you could maybe be able to exchange it at Haneda. I wouldn't count on it, though.