Best way from xiamen airport to mellinium harbour view hotel (downtown)?, 5 persosn+ bags? how much?

Well, the best way for you may be take taxi from the airport to the hotel, but you may need 2 taxis since there are 5 people in your group. The cost for one taxi is around CNY50.

For 1 pax, is there Airport Express Bus to Millenium Harbourview Xiamen Hotel pls?

If NO, do I disembark at some station where I could catch BRT to the Hotel - pls give me the names of (A) the Airport Express Bus Stop, (B) the BRT Station to board and (C) the BRT Station to get off (walking distance to Hotel pls).

Well, upon landing, you can take shuttle bus Ferry Boat Dock Line, get off at Ferry Boat Dock Station. It takes around 35 mins on the way. And the ticket fare is CNY 10 per person.
After arriving, just walk east along Zhongshan Road. Then walk southeast to get to your hotel. The total walking distance is about 0.6 miles.

Thank you very much, Kora, for your kind reply.