Kiso Valley in a day from Nagoya

Plan to cover this area in a day trip (november) with 3 kids aged below 10. Details as below:
Nagoya- train to Nakatsugawa-bus to Magome- trek to Tsumago-bus to Nagiso-Train back to Nagoya:

My questions:
1) Possible to do Kiso Valley from Nagoya in a day?
2) I am a JR pass holder, many said that Shinano limited express does not stop at Nagiso. Correct?
3)Alternative, will it be better if go and return via Nakatsugawa only? It mean i will trek from Magoma to Tsumago and take bus back from Tsumago to Magome.
4) Is the JR pass cover the bus ride from Nakatsugawa?
5) What is the best way to check whether the bus ride cover by JR pass or not? Or any website of JR bus ride will help?

Please advise. Thanks

Possible to do Kiso Valley from Nagoya in a day?

Yes, it is possible.

I am a JR pass holder, many said that Shinano limited express does not stop at Nagiso. Correct?

Most don't. A few do. Here are lists of those that do:
http://grace.hyperdia.com/cgi-english/hyperWeb.cgi?H_CM...
http://grace.hyperdia.com/cgi-english/hyperWeb.cgi?H_CM...

Alternative, will it be better if go and return via Nakatsugawa only? It mean i will trek from Magoma to Tsumago and take bus back from Tsumago to Magome.

No, the round trip options is better.

Is the JR pass cover the bus ride from Nakatsugawa?

No.

Thanks for your early reply.

Do try to establish bus and train times before you go. We did this last year ( based in Nagoya) and walked from Tsumago to Magome only to find that there were no buses for almost two hours.It cost us over Y3000 for a taxi to Nakatsugawa. Had we gone the other way a taxi from Tsumago to Nagiso would have been a lot less.
Another mystery was a bus at Nagiso station....I asked the driver if it was going to Tsumago and he said no and yet it stopped right next to our taxi when we got there (?)

Thanks Rob for your advise! it strenghterns my believe to do Magome-Tsumago instead.

BTW, UJI:

I like the "table form" of the train time table that you give me, that show train no & time to different station from my chosen departure and destination. (previous reply under the same thread) However, whenever i access Hypedia,i can only reach to the page as below:

http://grace.hyperdia.com/cgi-english/hyperWeb.cgi#TOP

1)Can you please advise me how to go to the summary page that present in a "table form" showing all the different train no and time, passing through different station before reaching the chosen destination? It helps a lot. Please forgive my long description. Hope you can understand what i mean.

thanks in advance

Look up a connection between the two stations. Then on the result page, click on the symbol that shows a blue clock over a book, and it will show you all the connections of the day.

Thanks you Uji! You save my day.
Cheers to you!