Where can we buy combination tickets?At JR stations across Japan.
And can we pay by credit card?
Yes. At some stations, you should tell the staff in advance that you intend to pay by credit card.
Where can we drop our luggages at Toyama and pick them up at Shinano-omachi? How much does it cost for same day service?
Drop off is at Toyama-Chitetsu Toyama Station before 9:30am. Pick up is at the Alps Roman building near Shinano-Omachi Station. i believe it is between 3pm (or 4pm?) and 6:30.
What will the lowest temperature during day time be?
It is not possible to make accurate 1-week weather forecasts. Here is some average data, which indicates 7 degrees lows for Murodo:
http://www.alpen-route.com/past/index.html
Can we get off from Highland Bus at any stop between Bijodaira and Murodo? If so, can we still use same ticket to get on another bus again? Or we need to buy new ticket?
As long as you do not back-track, you do not need a new ticket. I think there is only one stop along the way:
http://www.alpen-route.com/access/vehicle/vehicle02.htm...
What are recommended walking routes to see natures?
I recommend to see the Jigokudani Valley around Murodo. There are well marked round courses, that take between 30 and 60 minutes, I believe. If you want to hike more, you can easily extend the walk onto a nearby ridge or even summit.
Do we need to join guided tours?
No, these are easy walks along well maintained trails. They can be steep at times.
